Efficacy of ultra-micronized palmitoylethanolamide (um-PEA) in geriatric patients with chronic pain : study protocol for a series of N-of-1 randomized trials

Background: Chronic pain in older people is highly prevalent, often underestimated, and associated with adverse outcomes. Most available analgesic drugs are often either ineffective or not tolerated, with many side effects. Palmitoylethanolamide (PEA) is an endogenous widely distributed N-acylethanolamina involved in neuroinflammation and pain-generating processes. Formulations containing ultra-micronized palmitoylethanolamide (um-PEA) are available but their effectiveness on chronic pain in highly heterogeneous geriatric patients is not clear and probably not generalizable. We planned to adopt the N-of-1 trial approach to test the effectiveness of um-PEA objectively at the individual level in our older outpatients. Methods/Design: Persons 65 years or older referring to the Geriatric Unit of the Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico of Milan complaining of noncancer chronic pain of any origin will be eligible. Each trial will be a placebo-controlled randomized crossover trial including two um-PEA (600 mg twice a day) and placebo treatment pairs. The um-PEA or placebo 3-week periods will be separated by 2-week washout intervals to overcome possible carryover effects. Pain intensity, need of on-demand analgesic medications, and impact on daily activities will be evaluated. Cognitively impaired patients will be eligible as long as an expression of pain can be recognized and its frequency assessed by a caregiver. Trial results will be discussed with the patient or caregiver and the treating physician to decide whether to continue the treatment. The impact of the N-of-1 approach on the physician's management plan and confidence will be assessed. We will secondarily meta-analyze the performed N-of-1 trials to obtain an estimate of the average effect of um-PEA compared with placebo using a frequentist and Bayesian approach. Discussion: While pursuing an ultimate clinical objective, i.e. to empirically and objectively decide the best treatment choice for an individual older patient with chronic pain, these series of geriatric N-of-1 trials on PEA will bring the principles of evidence-based medicine into the care of patients not usually represented in conventional randomized controlled trials, and realize a patient-centered outcome approach necessary to improve appropriate prescribing in elderly patients with multimorbidity and polypharmacy. Trial registration: ClinicalTrials.gov NCT02699281. Registered on 3 March 2016

Late-Holocene climatic variability south of the Alps as recorded by lake-level fluctuations at Lake Ledro, Trentino, Italy

International audienceA lake-level record for the late Holocene at Lake Ledro (Trentino, northeastern Italy) is presented. It is based on the sediment and pollen analysis of a 1.75 m high stratigraphic section observed on the southern shore (site Ledro I) and a 3.2 m long sediment core taken from a littoral mire on the southeastern shore (site Ledro II). The chronology is derived from 15 radiocarbon dates and pollen stratigraphy. The late-Holocene composite record established from these two sediment sequences gives evidence of centennial-scale fluctuations with highstands at c. 3400, 2600, 1700, 1200 and 400 cal. BP, in agreement with various palaeohydro-logical records established in central and northern Italy, as well as north of the Alps. In addition, high lake-level conditions at c. 2000 cal. BP may be the equivalent of stronger river discharge observed at the same time in Central Italy's rivers. In agreement with the lake-level record of Accesa (Tuscany), the Ledro record also suggests a relatively complex palaeohydrological pattern for the period around 4000 cal. BP. On a millennial scale, sediment hiatuses observed in the lower part of the Ledro I sediment sequence indicate that, except for a high-stand occurring just after 7500 cal. BP, lower lake levels generally prevailed rather before c. 4000 cal. BP than afterwards. Finally, the lake-level data obtained at Lake Ledro indicate that the relative continuity of settlements in humid areas of northern Italy during the Bronze Age (in contrast to their general abandonment north of the Alps between c. 3450 and 3150 cal. BP), does not reflect different regional patterns of climatic and palaeohy-drological conditions. In contrast, the rise in lake level dated to c. 3400 cal. BP at Ledro appears to coincide with a worldwide climate reversal, observed in both the hemispheres, while palaeoenvironmental and archaeological data collected at Lake Ledro may suggest, as a working hypothesis, a relative emancipation of proto-historic societies from climatic conditions

Mutations of Glu92 in ferredoxin I from spinach leaves produce proteins fully functional in electron transfer but less efficient in supporting NADP+ photoreduction

4nononeFerredoxin I in spinach chloroplasts fulfils the role of distributing electrons of low redox potential produced by photosystem I to several metabolic routes, NADP+ reduction being the major output. To investigate the role of Glu92, which is conserved in the chloroplast-type ferredoxins, mutations of this residue to either Gln, Ala or Lys were obtained through site-directed mutagenesis. A Glu93Ala mutant was also designed. The four mutants of ferredoxin I were overproduced in Escherichia coli, purified and characterised. The different migration in nondenaturing gel electrophoresis of wild-type and mutant proteins confirmed that the desired mutation was present in the expressed proteins. Spectral and physical properties of the mutants were similar to those of wild-type ferredoxin; electron-transfer properties were, however, quite different in the case of the mutants at position 92. Unexpectedly, these mutant ferredoxins were found to be twice as active as the wild-type protein in supporting the NADPH-cytochrome c reductase reaction catalysed by ferredoxin-NADP+ reductase. However, interactions of the mutant ferredoxins with the isolated thylakoid membranes deprived of endogenous ferredoxin showed that the mutants were less capable of supporting NADP+ photoreduction than the wild-type protein: both V and the apparent K(m) for reduced ferredoxin were influenced. On the other hand, the K(d) values for the complex between oxidised ferredoxin and the reductase, measured at low ionic strength, were substantially changed only in the case of the Glu â Lys mutation. With this mutant the rate of cross-linking between the two proteins induced by a carbodiimide was lso decreased. It was found that the redox potentials of the iron-sulfur cluster of the mutants were more positive by 73-93 mV than that of ferredoxin I [Aliverti, A., Hagen, W.P. and Zanetti, O. (1995) FEBS Lett. 368, 220-224]. Thus, the behavior of the ferredoxin mutants can be rationalised in terms of the effect of the side-chain replacement on the electrochemical properties of the [2Fe-2S] cluster and of an impairment in the interaction with the reductase under physiological conditions.Piubelli, Luciano; Aliverti, Alessandro; Bellintani, Francesca; Zanetti, GiulianaPiubelli, Luciano; Aliverti, Alessandro; Bellintani, Francesca; Zanetti, Giulian

Archeologia sperimentale nell'archeologia italiana (con P.Bellintani, G.Chelidonio, L.Longo; atti del convegno tenutosi a in P.Bellintani, L.Moser (a cura di), Archeologie sperimentali. , Trento 2003, pp. 77-95.

Comano Terme-Fiav\ue8 dal 13 al 15 settembre 2001)