On the formation of a protic ionic liquid in nature.

The practical utility of ionic liquids (ILs) makes the absence (heretofore) of reported examples from nature quite puzzling, given the facility with which nature produces many other types of exotic but utilitarian substances. In that vein, we report here the identification and characterization of a naturally occurring protic IL. It can be formed during confrontations between the ants S. invicta and N. fulva. After being sprayed with alkaloid-based S. invicta venom, N. fulva detoxifies by grooming with its own venom, formic acid. The mixture is a viscous liquid manifestly different from either of the constituents. Further, we find that the change results as a consequence of formic acid protonation of the N centers of the S. invicta venom alkaloids. The resulting mixed-cation ammonium formate milieu has properties consistent with its classification as a protic IL.

Cervical length screening in patients who have undergone loop electrosurgical excision procedure.

OBJECTIVE: To determine whether cervical length measurements in patients who have undergone a loop electrosurgical excision procedure (LEEP) is a predictor of spontaneous preterm delivery (PTD) at < 35 weeks. STUDY DESIGN: A retrospective chart review of 97 pregnant patients with a history of prior LEEP undergoing cervical length screening by transvaginal ultrasound (TVUS) was done. Of these, 87 were included in the study. All patients delivered at the St. Luke's Hospital and Health Network over a 5-year study period. Cervical length measurements in the LEEP group were included. Incidence of PTD in patients who have undergone prior LEEP was compared to patients delivered during the same period who had not undergone LEEP. RESULTS: Of 87 patients who had undergone LEEP, 3 (3.4%, 95% CI 1.1-9.6%) delivered at < 35 weeks. None of the 3 patients had cervical shortening on TVUS. The PTD rate was not statistically different in the LEEP and non-LEEP groups. A shortened cervix was noted in 4 of the 87 patients in the LEEP group (4.5%, 95% CI 1.8-11%) but none had a PTD. CONCLUSION: Cervical length screening in LEEP patients may not be a predictor of PTD.