A high performance liquid chromatographic (HPLC) method was developed to determine the five endogenous hormones including indole-3-acetic acid (IAA), abscisic acid (ABA), gibberellic acid (GA3 ), zeatin (ZT) and salicylic acid (SA) in wheat. The separation conditions were optimized, and methanol was chosen as the extraction solvent. Then the extract was extracted by petroleum ether and ethyl acetate, and purified with the Sep-Pak C18 column. The chromatographic conditions were as follows: Eclipse XDB-C18 reversed phase column (250 mm x 4.6 mm, 5 microm), the flow rate of 1 mL/min, the injection volume of 10 microL, and the detection wavelength of 240 nm were used for the separation of SA from 14.5 min to 18 min, while the detection at 254 nm used for the separation of the others. Methanol (A) and acetic acid aqueous solution (pH 3.6) (B) were used as the mobile phases with the linear gradient set as follows: 0-7 min 20% A, 7-10 min 20% A-28% A, 10-17 min 28% A, 17-19 min 28% A-40% A, 19-35 min 40% A. The results showed that: the hormones were separated well with the recoveries of 96.9% - 98%, and the RSDs were in the range of 1.54% to 2.29%. It is a reliable method for rapid, accurate separation and determination of the endogenous hormones in wheat.

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Study Design. A cervical biomechanical study. Objective. We sought to demonstrate the three-dimensional (3D) intervertebral motion characteristics of the cervical spine in healthy volunteers using cone beam computed tomography (CBCT) combined with 3D-3D registration technology. Summary of Background Data. No previous studies have used CBCT combined with 3D-3D registration technology to successfully documented in vivo 3D intervertebral six-degreesof-freedom (6-DOF) motions of the cervical spine. Methods. Twenty healthy subjects underwent cervical (C1-C7) CBCT scans in seven functional positions. Segmented 3D vertebral body models were established according to the cervical CBCT images. A 3D-to-3D registration was then performed for each vertebral body in the different positions to calculate the 3D segmental motion characteristics in vivo. Results. During flexion-extension, the range-of-motion (ROM) of C1-C2 and C4-C5 was significantly greater than the other segments. The average coupled axial rotation and lateral bending of each segment were between 0.68 and 3.28. The average coupling translations in all directions were between 0.2 and 2.1 mm. During axial rotation, the ROM of C1-C2 was 65.8 AE 5.98, which accounted for approximately 70% of all axial rotation. The motion and displacement of C1-C2 coupled lateral bending were 11.4 AE 5.28 and 8.3 AE 1.9 mm, respectively. During lateral bending, the ROM of C3-C4 was significantly greater than C1-C2, C5-C6, and C6-C7. The coupled axial rotation of C1-C2 was 34.4 AE 8.18, and the coupled lateral translation was 3.8 AE 0.5 mm. The coupled superoinferior and anteroposterior translation of each cervical segment were between 0.1 and 0.6 mm. Conclusion. CBCT combined with 3D-3D registration was used to accurately measure and record the ROMs of lateral bending, axial rotation, and flexion-extension in cervical vertebrae under physiological-load conditions. Our findings may contribute to the diagnosis of cervical spinal disease, the development of new surgical techniques, and the restoration of normal, cervical segmental movement.

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Objective: The aim of this study was to measure the 3D motion of cervical vertebra with different curvatures under seven functional postures and investigate the relationship between cervical spine curvatures and the kinematics of each functional motion unit. Methods: Seventy-five volunteers were classified into 5 curvature groups based on the C1-C7 Cobb angle of sagittal alignment. These were: a normal group, straight group, kyphosis group and hyper and hypolordosis groups. All volunteers underwent cervical spine CBCT scans at 7 functional positions. The range-of-motion (ROM) of each vertebra and the overall cervical spine were measured using a 3D-3D registration technique. Results: In comparison to the normal group, the ROM of C3-C4 during left-right twisting in the kyphotic group was significantly higher, while the ROM of C1-C2 during left-right bending was also significantly greater. In addition, the ROM of C5-C6 in the straight group was higher during left-right bending in comparison to the normal group. During flexion-extension, the ROM of C4-C5 in kyphotic subjects was significantly lower than in the normal group, while in the C5-C6 segment, the ROM of the straight and the kyphotic groups was significantly greater compared to the normal group. During left-right bending, the global ROM of kyphotic subjects was higher than in the normal group. Conclusions: 3D kinematics was used to accurately quantify the ROM of cervical spine under different curvatures under physiological load. The data implied that cervical kyphosis may have a greater impact on ROM. Our findings may contribute to prevent cervical spondylosis by early intervention in curvature changes.