Protective Effect of Darodipine, a Calcium Antagonist, on Rat Cardiomyocytes against Oxygen Radical-Mediated Injury

1. We used electrophysiological and electron spin resonance (e.s.r.) techniques to study the mechanism of the protective effect of darodipine on rat isolated cardiomyocytes exposed to an exogenous source of oxygen free radicals (OFR). 2. The L-type calcium current (I(Ca,L)), action potential and cell shortening were measured in patch-clamped cells in the whole-cell configuration. I(Ca,L) blockade by darodipine was concentration-dependent, peak current being reduced by 20% with 50 nM and by 58% with 100 nM darodipine. The lowest concentration of darodipine did not affect action potential or twitch profile. 3. Exposure to OFR-generating solution (5 mM dihydroxyfumarate, DHF) caused the appearance of electrophysiological alterations and/or spontaneous activity in 73% of cells (n=26) within 5 min; action potential duration (APD) was prolonged (195±16 ms vs 140±6 ms in the control) and maximum diastolic potential (MDP) was reduced (−59.5±2.6 mV vs −69.8±0.8 mV in the control) (P<0.05, n=25). 4. A 2 min pretreatment with 50 nM darodipine significantly reduced the incidence of these arrhythmogenic events following a 5 min exposure to OFR (36% of cells, n=14; P<0.05 vs nonpretreated cells). Pretreatment with darodipine also prevented APD prolongation caused by OFR (137±12 ms after DHF vs 117±6 ms before DHF n=14, not significant) but not the decrease of MDP (−63.4±2.5 mV after DHF vs −70.9±1.0 mV before DHF, P<0.05). 5. The e.s.r. spectra obtained from the DHF-DMPO solution in the absence of darodipine demonstrated the presence of two components corresponding to two DMPO adducts. The addition of darodipine (50–500 nM) led to a concentration-dependent decrease in intensity of the signals, the intensity of the DMPO-COO.(−) adduct being decreased more than that of the DMPO-OH. adduct. 6. Our results demonstrate that darodipine dose-depentently blocks I(Ca,L) in rat isolated cardiomyocytes. Furthermore it exerts protective effects against free-radical-induced electrophysiological alterations independently of its calcium antagonistic properties; this effect is possibly due to trapping of specific radical species

An oral hygiene instruction program for orthodontic patients

Introduction. Protocols which contribute to the long-term success of orthodontic treatment, in both adult and young patients, and which establish a proper routine for oral hygiene at home, must be personalized and followed strictly. Materials and methods. Our protocol includes the following steps: before orthodontic treatment (initial examination, initial preparation and reassessment); during orthodontic treatment (first session, treatment session in association with oral hygiene check-ups, recall, if oral hygiene is insufficient); after orthodontic treatment (postreatment support). The differences in treatment and approach necessary when dealing with adults or children and with removable appliance or fixed appliance are also highlighted

The World Justice Project. Rule of Law Index 2012-2013 Report (Italy)

The Goal of The World Justice Project (WJP) is to advance the rule of law around the world. To be effective rule of law development requires clarity about the fundamental features of the rule of law as well as an adequate basis for its evaluation and measurement. The WJP Rule of Law Index 2012-2013 Report looks at 48 rule of law indicators organized around nine conceptual dimensions, relating to over 100 countries in the world (including Italy