Trigeminal Chemesthesis

In the present chapter we will summarize some important functional properties of the human trigeminal chemosensory system in the nasal, ocular and oral mucosae. Among others, we will address issues related to candidate molecular receptors for trigeminal chemesthesis, chemesthetic sensitivity (i.e., detection thresholds), structure-activity relationships, detection of chemical mixtures, and temporal properties of trigeminal chemesthetic sensations

Laser Removal of Cosmetic Eyebrow Tattoos with a Picosecond Laser

This current retrospective study, including 98 patients aged 21 to 71 years, aims to assess the safety and the efficiency of a picosecond 755 nm/532 nm laser in the removal of complex eyebrows tattoos. Patients were treated with a picosecond laser at 755 nm with fluences ranging from 0.69 to 6.37 J/cm2 and at 532 nm with a fluence of 0.64 or 1.12 J/cm2. Analyses of Variance (ANOVA, single factor) and comparison tests (F-test) were conducted. A total of 70 subjects finished the full treatment. An average of three laser sessions were necessary to achieve the patients’ objective (total removal, attenuation for redo, or correction). The number of sessions was significantly higher if cosmetic tattoos contained visible warm pigments (red, orange, yellow). A total of 18 patients experienced immediate grey discoloration, although this was not found to significantly influence the number of laser sessions. The main side effects were redness, swelling, and bleeding points. One patient experienced a bruise immediately after laser shots. This retrospective study has shown the picosecond laser to be safe and efficient in removing complex cosmetic tattoos. Further investigation is ongoing to assess optimal parameters for treating red and white pigments

Compounds from Sichuan and Melegueta peppers activate, covalently and non-covalently, TRPA1 and TRPV1 channels

Background and purpose

Inhibition of hydroxycinnamic acid sulfation by flavonoids and their conjugated metabolites

Hydroxycinnamic acids and flavonoids are dietary phenolic antioxidants that are abundant in our diet. Hydroxycinnamic acids are highly sulfated in vivo, and sulfotransferases (SULTs), in particular SULT1A1, play a major role in their metabolism. Flavonoids are potent inhibitors of human SULTs. In this study, the potential metabolic interaction between dietary hydroxycinnamic acids and flavonoids was investigated. Flavonoids, such as luteolin, quercetin, daidzein, and genistein, are identified as potent inhibitors of hydroxycinnamic acid sulfation in human liver S9 homogenate with IC values <1 μM. The inhibitory activity was less potent in the human intestinal S9 homogenate. We also demonstrate that quercetin conjugates found in vivo (quercetin-3-O-glucuronide, quercetin-7-O-glucuronide, and quercetin-3'-O-sulfate) moderately inhibited the sulfation of hydroxycinnamic acids in human liver S9. In an intact cellular system, human HepG2 cells, caffeic acid and ferulic acid sulfation was inhibited by luteolin and quercetin (IC: 1.6-3.9 μM). Quercetin-3'-O-sulfate weakly inhibited sulfation. Quercetin glucuronides, limited by their low cellular uptake, were ineffective. These data suggest that the inhibition of SULTs by flavonoids and in vivo flavonoid conjugates may modify the bioavailability of dietary hydroxycinnamic acids by suppressing their conversion to sulfated metabolites