[The application of subjective visual gravity in assessment of vestibular compensation: a pilot study].

OBJECTIVE: To discuss the characteristics of subjective visual gravity (subjective visual vertical/horizontal, SVV/SVH) and assess its clinical application for peripheral unilateral vestibular compensation. METHODS: 69 cases of acute peripheral unilateral vestibular dysfunction patients (case group) accepted SVV/SVH, spontaneous nystagmus (SN), caloric test (CT) and other vestibular function tests. 49 healthy people (control group) accepted SVV/SVH only. SVV/SVH, SN and unilateral weakness (UW) were selected as for the observation indicators. The correlations between SVV/SVH, SN, UW and courses were investigated respectively, as well as the characteristic of SVV/SVH, SN in period of vestibular compensation. RESULTS: Among case group SVV, SVH positive in 42 patients(60.9%) and 44 patients(63.8%), the absolute values of the skew angle were in the range between 2.1°-20.0°, 2.1°-22.2°. Skew angles of SVV/SVH in control were in the range between -1.5°-2.0° and -2.0°-1.6°, and had no statistical significance with case group(t=5.336 and 5.864, P<0.05). SN-positive 28 cases (40.6%), the range of intensities at 2.4°-17.1°; UW-positive 50 cases (72.5%). In case group, positive correlation between SVV and SVH(r=0.948, P=0.00), negatively correlated between SVV/SVH and SN respectively(r values were -0.720, -0.733, P values were 0.00), no correlation between the skew angle of SVV/SVH, strength of SN and UW value(r values were 0.191, 0.189, and 0.179, P>0.05), there was no correlation between the absolute value of SVV, SVH, SN, UW with the duration (rs values were -0.075, -0.065, -0.212, and 0.126, P>0.05). CONCLUSION: Subjective visual gravity can be used not only to assess the range of unilateral peripheral vestibular dysfunction, but also help assess the static compensatory of otolithic, guidance and assessment of vestibular rehabilitation.

Crystal violet-G-quadruplex complexes as fluorescent sensors for homogeneous detection of potassium ion.

A novel K(+) detection method was reported using a label-free G-quadruplex-forming oligonucleotide and a triphenylmethane fluorescent dye crystal violet (CV). This method is based on the fluorescence difference of some CV/G-quadruplex complexes in the presence of K(+) or Na(+), and the fluorescence change with the variation of K(+) concentration. According to the nature of the fluorescence change of CV as a function of ionic conditions, two K(+) detection modes can be developed. One is a fluorescence-decreasing mode, in which T(3)TT(3) (5'-GGGTTTGGGTGGGTTTGGG) is used, and the fluorescence of CV decreases with an increased concentration of K(+). The other is a fluorescence-increasing mode, in which Hum21 (5'-GGGTTAGGGTTAGGGTTAGGG) is used, and the fluorescence of CV increases with an increased concentration of K(+). Compared with some published K(+) detection methods, this method has some important characteristics, such as lower cost of the test, higher concentrations of Na(+) that can be tolerated, adjustable linear detection range and longer excitation and emission wavelengths. Preliminary results demonstrated that the method might be used in biological systems, for example in urine.