β-Citronellol,an alcoholic monoterpene with inhibitory properties on the contractility of rat trachea

β-Citronellol is an alcoholic monoterpene found in essential oils such Cymbopogon citratus (a plant with antihypertensive properties). β-Citronellol can act against pathogenic microorganisms that affect airways and, in virtue of the popular use of β-citronellol-enriched essential oils in aromatherapy, we assessed its pharmacologic effects on the contractility of rat trachea. Contractions of isolated tracheal rings were recorded isometrically through a force transducer connected to a data-acquisition device. β-Citronellol relaxed sustained contractions induced by acetylcholine or high extracellular potassium, but half-maximal inhibitory concentrations (IC₅₀) for K⁺-elicited stimuli were smaller than those for cholinergic contractions. It also inhibited contractions induced by electrical field stimulation or sodium orthovanadate with pharmacologic potency equivalent to that seen against acetylcholine-induced contractions. When contractions were evoked by selective recruitment of Ca²⁺ from the extracellular medium, β-citronellol preferentially inhibited contractions that involved voltage-operated (but not receptor-operated) pathways. β-Citronellol (but not verapamil) inhibited contractions induced by restoration of external Ca²⁺ levels after depleting internal Ca²⁺ stores with the concomitant presence of thapsigargin and recurrent challenge with acetylcholine. Treatment of tracheal rings with L-NAME, indomethacin or tetraethylammonium did not change the relaxing effects of β-citronellol. Inhibition of transient receptor potential vanilloid subtype 1 (TRPV1) or transient receptor potential ankyrin 1 (TRPA1) receptors with selective antagonists caused no change in the effects of β-citronellol. In conclusion, β-citronellol exerted inhibitory effects on rat tracheal rings, with predominant effects on contractions that recruit Ca²⁺ inflow towards the cytosol by voltage-gated pathways, whereas it appears less active against contractions elicited by receptor-operated Ca²⁺ channels.     

Is there an association between overweight/obesity and dental implant complications? A systematic review and meta-analysis

The aim of this systematic review was to test the following hypotheses: (1) that there is no difference in implant survival rate between individuals with overweight or obesity and those who are within the ideal weight range; (2) that there are no differences between these groups regarding indicators of peri-implant health. Two independent reviewers performed a literature search of the PubMed/MEDLINE, Scopus, and Cochrane Library databases for studies published up to April 1, 2018. A meta-analysis was performed to determine the risk difference for implant failure and mean difference for marginal bone loss, probing depth, and bleeding on probing. Six studies were selected for review, involving a total of 746 patients with 986 implants: 609 in overweight or obese individuals and 377 in individuals within the ideal weight range. The findings of this systematic review indicate that the first hypothesis should be accepted, since no statistically significant difference in implant survival rate was found between individuals with overweight/obesity and those within the ideal weight range (P = 0.64). The second hypothesis was rejected, as the review indicated a difference in marginal bone loss (P < 0.00001), probing depth (P < 0.00001), and bleeding around dental implants (P < 0.00001).     

Revisiting epilepsy and the electroencephalogram patterns in Angelman syndrome

Angelman syndrome is a neurogenetic disorder that severely affects global neurodevelopment due to modifications in the structure or functioning of UBE3A gene. Its prevalence ranges from 1:10,000 to 1:40,000. There are four main genetic types of AS transmission. A maternal deletion in 15q11.2-q13 is the most common type. There are three well-established electroencephalogram (EEG) patterns used as an ancillary tool for AS diagnosis. The main objectives are to scrutinize the EEG patterns in Angelman syndrome, their correlation to different types of seizures and to review the role of the EEG as an ancillary screening tool in the diagnosis of clinically suspected patients. Forty-three patients’ charts and their previously recorded EEGs were reviewed. A set of 34 patients with deletion type, paternal uniparental disomy type and imprint defect type AS were enrolled. AS diagnosis was confirmed either by fluorescent in situ hybridization test or Methylation Specific–Multiplex Ligation Probe Amplification test. Sequencing of UBE3A was not available. Frequencies and Chi-square tests were used for statistic analysis. Pattern I type EEG was observed in 22 (64.7 %) individuals. Pattern II accounted for 6 (17.6 %); Pattern III was evident in 11 (32.4 %). The three distinguished EEG patterns, more frequently Pattern I, when observed in the appropriate clinical setting, may heighten the index of suspicion for selecting patients who will need a molecular biology test to confirm the diagnosis of AS.