A matched-filter algorithm to detect amperometric spikes resulting from quantal secretion.
A matched-filter algorithm to detect amperometric spikes resulting from quantal secretion.
复制标题
一种匹配滤波器算法，用于检测量子分泌产生的电流尖峰。
DOI：
10.1016/j.jneumeth.2017.10.019
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发表时间：
2018
影响因子：
3
通讯作者：
Gillis,KevinD
中科院分区：
文献类型：
--
作者：
BalajiRamachandran,Supriya;Gillis,KevinD
背景当单个囊泡释放的递质在电极表面被氧化时，紧邻细胞表面的电化学微电极可以检测胞吐作用期间电流的尖峰。需要自动化技术来检测尖峰，以便量化尖峰速率作为胞吐速率的度量。新方法我们开发了一种匹配滤波器（MF）检测算法，该算法使用原型尖峰模板库扫描数据集，同时执行最小二乘拟合以确定幅度和标准误差。拟合幅度与标准误差的比率构成为每个时间点和每个模板分配的标准分数。当标准分数超过阈值时检测到峰值，并识别最高分数模板和峰值分数的时间。仅在分数低于第二个较低阈值以减少误报后，才会开始搜索下一个峰值。该方法被扩展到用两个模板的总和来检测具有双指数衰减的尖峰。结果接收器操作特性图（ROC）表明该算法检测到> 95％的手动识别的尖峰，假阳性率为~2％。与现有方法的比较ROC表明MF算法比基于导数阈值方法检测尖峰的算法表现更好。结论MF方法表现良好，并导致了识别尖峰参数的方法。
BackgroundElectrochemical microelectrodes located immediately adjacent to the cell surface can detect spikes of amperometric current during exocytosis as the transmitter released from a single vesicle is oxidized on the electrode surface. Automated techniques to detect spikes are needed in order to quantify the spike rate as a measure of the rate of exocytosis.New methodWe have developed a Matched Filter (MF) detection algorithm that scans the data set with a library of prototype spike templates while performing a least-squares fit to determine the amplitude and standard error. The ratio of the fit amplitude to the standard error constitutes a criterion score that is assigned for each time point and for each template. A spike is detected when the criterion score exceeds a threshold and the highest-scoring template and the time of peak score is identified. The search for the next spike commences only after the score falls below a second, lower threshold to reduce false positives. The approach was extended to detect spikes with double-exponential decays with the sum of two templates.ResultsReceiver Operating Characteristic plots (ROCs) demonstrate that the algorithm detects >95% of manually identified spikes with a false-positive rate of ∼2%.Comparison with existing methodsROCs demonstrate that the MF algorithm performs better than algorithms that detect spikes based on a derivative-threshold approach.ConclusionsThe MF approach performs well and leads into approaches to identify spike parameters.