Utilization of the Lempert Maneuver for Benign Paroxysmal Positional Vertigo in the Emergency Department.

Benign paroxysmal positional vertigo (BPPV) is a common cause of vertigo. Symptoms from BPPV lead to Emergency Department (ED) visits, and persistence of symptoms, particularly in the elderly, may impact patient disposition. We describe the techniques used in the case of a 72-year-old male with dizziness, who had symptom resolution, and was able to be safely discharged after a Lempert maneuver (barbeque (BBQ) roll) was performed in the ED setting. The patient presented to the ED with left gaze nystagmus, and otherwise normal evaluation results. Physical therapy was consulted, and their initial evaluation indicated right horizontal canalithiasis noted by fatiguing right, geotropic nystagmus, but the patient was unable to tolerate further testing due to vomiting. Antiemetic medications were administered and at his follow-up examination an hour later, a total of three Lempert maneuvers were performed, resulting in total symptom resolution. Successful utilization of the Lempert maneuver to treat BPPV can help to reduce ED length of stay and increase patient satisfaction. Because of this, the Lempert maneuver should be considered a fast, cost-effective, and safe method of alleviating BPPV symptoms

Phenotypic effects of changes in the FTVTxK region of an Arabidopsis secondary wall cellulose synthase compared with results from analogous mutations in other isoforms

Understanding protein structure and function relationships in cellulose synthase (CesA), including divergent isomers, is an important goal. Here, we report results from mutant complementation assays that tested the ability of sequence variants of AtCesA7, a secondary wall CesA of Arabidopsis thaliana, to rescue the collapsed vessels, short stems, and low cellulose content of the irx3-1 AtCesA7 null mutant. We tested a catalytic null mutation and seven missense or small domain changes in and near the AtCesA7 FTVTSK motif, which lies near the catalytic domain and may, analogously to bacterial CesA, exist within a substrate “gating loop.” A low-to-high gradient of rescue occurred, and even inactive AtCesA7 had a small positive effect on stem cellulose content but not stem elongation. Overall, secondary wall cellulose content and stem length were moderately correlated, but the results were consistent with threshold amounts of cellulose supporting particular developmental processes. Vibrational sum frequency generation microscopy allowed tissue-specific analysis of cellulose content in stem xylem and interfascicular fibers, revealing subtle differences between selected genotypes that correlated with the extent of rescue of the collapsing xylem phenotype. Similar tests on PpCesA5 from the moss Physcomitrium (formerly Physcomitrella) patens helped us to synergize the AtCesA7 results with prior results on AtCesA1 and PpCesA5. The cumulative results show that the FTVTxK region is important for the function of an angiosperm secondary wall CesA as well as widely divergent primary wall CesAs, while differences in complementation results between isomers may reflect functional differences that can be explored in further work