Effects of Footbaths with Mustard, Ginger, or Warm Water Only on Objective and Subjective Warmth Distribution in Healthy Subjects: A Randomized Controlled Trial

Objective: To analyze the short-term thermogenic effects of footbaths with warm water alone (WA) versus when combined with medicinal powders. Design: Randomized controlled trial with cross-over. Interventions and Outcomes: Seventeen healthy volunteers (mean age 22.1 years, SD = 2.4; 11 female) received three footbaths with WA or WA combined with mustard (MU) or ginger (GI) in a randomized order. Self-perceived warmth (Herdecke warmth perception questionnaire) and actual skin temperatures (thermography) were assessed before (t0), immediately after footbaths (t1), and 10 minutes later (t2). The primary outcome was perceived warmth in the feet. Secondary outcomes were warmth perception in the face, hands and overall, as well as actual skin temperature in the feet, face, and hands. Results: Perceived warmth at the feet (primary outcome) increased significantly (all p\u27s \u3c.001) for MU and GI at t1 as well as for GI at t2 when compared to t0 with high effect sizes. At t2, GI differed significantly from WA (p \u3c.001) and MU (p =.048). With regards to the secondary measures of outcome, no significant effects were seen for perceived warmth at the face or hands. Overall warmth was significantly higher at t1 compared to t0 (p =.01). Thermography assessments of skin temperature at the feet at t1 increased after all conditions (p \u3c.001). No effects were seen in the face. At the hands, temperature decreased at t1 (p =.02) and t2 compared to t0 (p \u3c.001). Conclusion: The present study provides preliminary evidence that mustard and ginger increase warmth perception at the feet more than warm water alone, with only the effects for GI enduring at the brief follow-up

Activation of terminal alkynes by frustrated lewis pairs

The reactions of frustrated Lewis pairs (FLPs) derived from B(C6F5)3 and the bulky Lewis bases 2,2,6,6-tetramethylpiperidine (TMP), tri-tert-butylphosphine, and lutidine (Lut) with terminal alkynes (acetylene, phenylacetylene, 3-ethynylthiophene) were investigated. The FLPs TMP center dot center dot center dot B(C6F5)(3), t-Bu3P center dot center dot center dot B(C6F5) and Lut center dot center dot center dot(C6F5) reacted with acetylene (HC CH) to yield the apparently thermodynamically more stable E isomers TMPH](C6F5)(2)B-C(C6F5)=C(H)B(C6F5)(3)] (1-E), t-Bu3PC(H)=C(H)B(C6F5)(3) (2-E; 90%), and t-Bu3PH](C6F5)(2)B-C(C6F5)=C(H)B(C6F5)(3)] (3-E; 10%),and LutC(H)=C(H)B(C6F5)(3) (4-E), respectively. A mechanistic pathway for the reaction of acetylene is suggested to start with the formation of a weak B(C6F5)(3)/acetylene adduct followed by it deprotonation of this species with any mentioned Lewis bases (LB), yielding the acetylicle salts LBH](C6F5)(3)BC CH]. Alternatively, nucleophilic addition of the LB to this adduct occurs to yield LBC(H)=C(H)B(C6F5)(3) compounds. Formation of 1 and 3-E is explained by the reactions of LBH]B(C6F5)(3)C CH] salts with a second equivalent of B(C6F5)(3) to undergo clectrophilic addition, forming the vinylidene adduct (C6F5)(3)B-C+=C(H)B(C6F5)(3), which is subsequently stabilized by 1,2-migration Of a C6F5 group to form (C6F5)(2)BC(C6F5)=C(H)B(C6F5)(3)]. The reaction between B(C6F5)(3) and phenylacetylene yielded a mixture of (Z)- and (E)-PhC(H)=C(C6F5)B(C6F5)(2) (11-Z and 11-E), confirming that the reaction proceeds via an acetylene/vinylidene rearrangement and subsequent 1,2-shift of a C6F5 group to the carbenic center. The FLPs TMP center dot center dot center dot B(C6F5)(3) and tBu(3)P center dot center dot center dot B(C6F5)(3) were converted with phenylacetylene or 3-ethynylthiophene to yield the acetylide products TMPH]PhC CB(C6F5)3] (5), TMPH]SC4H3C CB(C6F5)(3)] (6), t-BU3PH]PhC CB(C6F5)(3)] (7), and t-Bu3PH]SC4H3C=CB(C6F5)3] (8), where TMP and t-Bu3P acted as a base deprotonating the acetylenic proton. When the FLP Lut center dot center dot center dot B(C6F5)(3) was reacted with phenylacetylene or 3-ethynylthiophene, the deprotonated product LutH]PhC CB(C6F5)(3)] (9; 47%) and the 1,2-addition compound LutC(SC4H3C)=C(H)B(C6F5)(3) (10; 55%) were obtained. Compounds 1-E, 2-E, 5, and 6 were characterized by X-ray diffraction studies