ABSTRACT
OBJECTIVE： To establish the method for the content determination of related substance in Terazosin hydrochloride tablets. METHODS： HPLC and principal component self-control with correction factor were adopted. The determination was performed on Agilent Zorbax Eclipse XDB C18 column with mobile phase consisted of acetonitrile-perchloric acid solution （20 ∶ 80， V/V） at the flow rate of 1.0 mL/min. The detection wavelength was set at 246 nm， and sample size was 20 μL. The column temperature was 50 ℃. The linear equations of terazosin hydrochloride， impurity A， B， C were drawn. The correction factors of each impurity related to terazosin hydrochloride were calculated by slope， and relative retention time was used to determine the position of impurities. The contents of impurity A， B and C in 3 batches of Terazosin hydrochloride tablets were determined and compared with the results of impurity control method. RESULTS： The relative retention time of impurity A， B， C was 0.39， 0.74， 2.77， respectively； the linear range of them were 0.25-3.0 μg/mL， respectively. The correction factors were 0.75， 1.09， 0.84， respectively. The detection limits were 0.35， 0.51， 0.43 ng， and the limits of quantification were 0.70， 1.02， 0.86 ng， respectively. The contents of impurity A， B and C in 3 batches of Terazosin hydrochloride tablets were 0.11％-0.13％， 0.03％ and 0.09％-0.12％； impurity B did not detected. The results are consistent with the determination of impurity control method. CONCLUSIONS： The method is simple， rapid and accurate for the content determination of related substances A， B， C in Terazosin hydrochloride tablets.
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Objective To evaluate the feasibility and efficacy of posterior enlargement of spinal canal for the treatment of multi-segmental cervical diseases without cervical lordosis.Methods From January 2013 to June 2017,a retrospective study was conducted with 21 patients of multi-segmental cervical diseases accompanied cervical lordosis loss,and the complete followup data was obtained.There were 14 males and 7 females,with an average age of 53.9±7.3 years (range,42-65 years).There were 14 multi-segmental cervical spondylotic myelopathy,5 ossification of posterior longitudinal ligament,and 2 congenital cervical stenosis included in this study.The cervical lordotic angle and cervical curvature index were measured preoperatively and 1 year postoperatively.To access the enlargement of spinal canal and spinal cord,the anteroposterior diameter and cross section area of spinal canal or spinal cord were measured on MRI preoperatively and 1 year postoperatively.The Japanese Orthopaedic Association Scores (JOA) was applied to evaluate the neurological function at preoperation and postoperation.Visual Analogue Scales (VAS) was applied to evaluate the pain degree at preoperation and postoperation.Frankel classification was used to assess the severity of spinal cord injury at preoperation and postoperation.Results The follow-up time was 12-26 months,with an average of 16.4 months.The cervical lordosis angle was 3.1°±2.3° preoperatively,and 4.2°±1.6° 1 year postoperatively with a significant difference.The cervical curvature index was 4.4％ ± 1.7 ％ preoperatively and 5.0％ ± 1.5 ％ 1 year postoperatively with no statistically difference.Except for C7T1 level,the preoperative anteroposterior diameter and cross section area of spinal canal at C2.3,C3.4,C4.5,C5.6,and C6.7 level were lower than that at 1 year after operation with a significant difference.Except for C2,3 and C7T1 and level,the preoperative anteroposterior diameter and cross section area of spinal cord at C3,4,C4,5,C5,6,and C6,7 level were significantly lower than that at 1 year after operation.The average JOA score preoperatively was 8.9±1.7.The average JOA score at 3 months postoperatively was 13.1±2.0,which was significantly higher than that preoperatively.At 3 months postoperatively,the average improvement rate was 52.0％,and the superior rate was 52.3 ％.At 1 year postoperatively,the average JOA score was 13.3±2.1,which improved significantly from that preoperatively.The average improvement rate was 54.3 ％,and the superior rate was 61.9％.The VAS score at preoperatively was 3.0±2.4,and which was 2.7± 1.7 at 1 year postoperatively with no significant differences.At pre-operation,the level of Frankel classification was C level in one (4.8％) case,D level in 8 (38.1％) cases and E level in 12 (57.1％) cases.At 1 year postoperatively,the level of Frankel classification was C level in one (4.8％) case,D level in 6 (28.6％) cases and E level in 14 (66.7％) cases,compared with that at preoperatively,there was no statistically significant difference.One patients suffered from neurologic deterioration at 1 year after surgery and recovered after anterior cervical surgery.No other serious complications were occurred.Conclusion For the patients with multi-segmental cervical diseases accompanied cervical lordosis loss,effective spinal decompression by cervical posterior laminoplasty was feasible,and a good clinical efficacy was achieved.
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Objective To study the anatomic features of surface vasa vasorum on longissimus in thoracolumbar segments,and its protection function during the internal fixation for thoracolumbar fracture via Wiltse approach.Methods From March 2010 to October 2012,a total of 97 patients with thoracolumbar fractures underwent posterior internal fixation with pedicle screw system.The trend and distribution of surface vasa vasorum on longissimus in thoracolumbar segments were observed in the operation,and the vessels were protected during the surgical procedures by using specific devices and techniques.Operative time and intra-operative blood loss were recorded.Visual analogue scale (VAS) values were evaluated after 3 days,1 month,6 months postoperatively,and 1 month after the removal of internal fixation.MRI images of longissimus in thoracolumbar segments were compared after preoperative and postoperative 6 months.Results Surface vasa vasorum distribution on 194 longissimus and 402 inter-pedicle areas of 97 patients were observed.In 402 areas,94.3％ of surface vasa vasorum presented sarciniform,while only 5.7％ of surface vasa vasorum presented tube shape.In 379 areas of sarciniform distribution,9.8％ of blood vessel bundles were located in vertebral pedicle area;76.0％ of blood vessel bundles were located in the upper inter-pedicle areas;12.4％ of blood vessel bundles were located in middle inter-pedicle areas;1.8％ of blood vessel bundles were located in lower inter-pedicle areas.In 379 areas,87.3％ of blood vessel bundles could be completely retained;12.7％ of blood vessel bundles were treated by electro coagulation and burning.Intra-operative blood loss was 21±9.3 ml.VAS values after 3 days,1 month,6 months postoperatively,and 1 month after the removal of internal fixation were 3.3± 1.6,2.1± 1.4,1.2±0.7 and 1.1±0.7.The longissimus treated with electro coagulation demonstrated pimelosis change on MRI after postoperative 6 months.Conclusion Surface vasa vasorum on longissimus in thoracolumbar segments are generally of sarciniform,and most of them are located in upper inter-pedicle areas.The protection of vasa vasorum can reduce the intra-operative lesion and postoperative pimelosis change of longissimus.