[The potential application of a three-dimensional visualization technique in adrenal vein sampling].

Objective: To explore the potential application of a three-dimensional visualization technique in adrenal vein sampling (AVS). Methods: The clinical data were retrospectively analyzed, which included 76 patients with primary aldosteronism (PA) who have undergone AVS in Guizhou Provincial People's Hospital from December 2017 to May 2020. All cases were examined by adrenal thin-section enhanced CT and blood was drawn by bilateral AVS. Among them, the adrenal vein blood of 46 cases was sampled with the help of three-dimensional (3D) visualization processing of CT data, while that of 30 cases was without 3D visualization processing. The rate of the catheter in place, the successful rate of AVS, the time of blood collection, the dosage of the contrast agent, and surgical complications were compared between the two groups. Results: There were 76 cases included, while 38 were male and 38 were female. The average age was 45 (25-57) years. Compared with the patients without the aid of 3D visualization, the success rate of right AVS of the patients with the aid of 3D visualization technology increased from 43% to 78% (P<0.05). The success rate of adrenal vein blood collection increased from 53% to 83%. The dose of contrast agent decreased [the M(Q1,Q3) were78 (59, 89) ml vs 28 (16, 51) ml, P<0.05], and the time of blood sampling from the right adrenal vein approximately decreased [the M（Q1，Q3） were 70 (66, 88) min vs 44 (22, 61) min, P<0.05]. Compared with the case without the aid of 3D visualization, the left adrenal vein catheterization rate of patients in the 3D visualization group increased from 97% to 98%, the success rate of adrenal vein blood collection increased from 97% to 98%, and the differences of the time of blood sampling and the dosage of the contrast were not statistically significant between the two groups. Among all the cases experienced bilateral AVS, only one patient without 3D reconstruction had contrast extravasation, and the others had no obvious complications. Conclusions: Before AVS, 3D visualization processing of adrenal vein from CT data is capable of increasing the success rate of blood sampling from the right adrenal vein, as well as reducing the dosage of contrast agent and the time of adrenal vein blood sampling. Therefore, it has a potential clinical value of the application.

Forward masking effects on early auditory evoked potentials.

In early auditory evoked potentials (EAEPs) evoked by click trains, every click had a masking effect on the responses to the clicks following it and the whole response evoked by the click train was the sum of the masked responses to every click in the train. Special attention was paid to the situation when the inter-stimulus interval (ISI) was less than 10 ms and the responses to the individual clicks might be merged to form a continuous wave. The experiments showed that the more the number of the clicks preceding a given click in the train, the stronger the effect on the response to this click until the number was big enough and the effect became saturated; the shorter the ISI when it was less than 10 ms, the stronger the effect; the higher the intensity of the masker, the stronger the effect.

A quantitative model of myosin phosphorylation and the photomechanical response of the isolated sphincter pupillae of the frog iris.

The time courses of isometrically recorded photomechanical responses of isolated sphincter pupillae of Rana pipiens can be accurately predicted by a set of differential equations derived from phosphorylation theory of smooth muscle contraction. We compared actual light-stimulated contractions with calculated ones over a wide range of stimulus intensities (56-fold) and durations (0.4-4.0 s). The hypothetical Ca++-calmodulin-myosin light chain kinase cascade acts as a "valve" to control the flow of ATP through a phosphorylation-dephosphorylation cycle. When the rate of flow of ATP through the phosphorylation-dephosphorylation cycle is increased, the percentage of phosphorylated myosin increases. The time courses of the concentrations of phosphorylated myosin during different responses are seen to be functions of the time courses of the opening and closing of the coupling cascade "valve." The calculations predict experimentally measurable intermediate variables, which can aid the investigation of the application of quantitative phosphorylation theory to amphibian sphincter pupillae and to smooth muscle in general.