LC-MS/MS法测定人血浆中布康唑浓度的不确定度评定

目的：评定LC-MS/MS法测定人血浆中布康唑浓度的不确定度。方法：分析测定过程中不确定度的来源，包括对照品的称量、仪器误差、标准溶液的配制、含药血浆样品的配制、血浆样品的处理、标准曲线的拟合、基质效应、重复性等，评定各来源分量的不确定度，计算合成不确定度和扩展不确定度。结果：人血浆中低（60.0 pg·mL^-1）、中（600.0 pg·mL^-1）、高（6 400.0 pg·mL^-1）浓度布康唑的扩展不确定度分别为5.62，63.90，626.26 pg·mL^-1（k=2，P=95%）。结论：LC-MS/MS法测定人血浆中布康唑浓度的不确定度主要由基质效应、血浆样品的处理（提取回收率），仪器误差、重复性（精密度）引入。     

Effect of a Condom Cover on Vaginal Photoplethysmographic Responses

IntroductionThe vaginal photoplethysmograph (VPP) is a reusable intravaginal device often employed in sexual psychophysiology studies to assess changes in vaginal blood flow, an indicator of sexual arousal.AimTo test whether placing a disposable cover on the VPP probe impacts the acquired data. A condom cover would reduce risk of disease transmission and likely increase participant comfort but may negatively impact the VPP signal.MethodThe genital responses of 25 cisgender women (mean age = 21.3 years, standard deviation = 2.6) were assessed with VPP in a within-subjects design with 2 conditions—with and without a polyisoprene condom cover. Sexual responses were elicited by audiovisual film clips that varied in erotic intensity: nonsexual (nonsexual male-female interaction), low-intensity sexual (nude exercise), and high-intensity sexual (male-female intercourse). Women continuously rated their sexual arousal during stimulus presentations.Main Outcome MeasureChange in vaginal pulse amplitude and also self-reported sexual arousal.ResultsThe magnitude of sexual response to each stimulus category and the overall pattern of results were found to be highly similar in the cover-off and cover-on conditions. The high-intensity sexual stimulus category elicited a greater sexual response than all other categories. The low-intensity sexual category elicited a (small) genital response in only the cover-on condition, although we suspect this is a spurious finding. There was no difference in the average number of edited movement artifacts across conditions.Clinical ImplicationsPotential benefits of encasing the VPP probe with a protective cover include enhanced participant safety and comfort, especially if assessing genital responses of high-risk or immunocompromised samples. The use of a cover complies with current guidelines for reprocessing semi-critical medical devices (eg, vaginal ultrasound probes) in many regions.Strengths & LimitationsAlthough the idea of a VPP probe cover had been discussed among sexual psychophysiology researchers, this is the first study to empirically test whether a cover could jeopardize VPP data. Potential limitations include the use of a 10-Hz VPP sampling rate and a cover that was not tailored to the size of the VPP probe.ConclusionPlacing a protective cover on the VPP probe did not appear to meaningfully impact sexual arousal or the VPP data. Based on these results and the potential advantages of a protective cover, researchers may wish to integrate the use a condom cover in their experiment protocols and clinical applications.Sawatsky ML, Lalumière ML. Effect of a Condom Cover on Vaginal Photoplethysmographic Responses. J Sex Med 2020; 17:702–715.