1.A Low Noise Amplifier System for Nanopore-based Single Molecule Analysis
Bingyong YAN ; Zhen GU ; Rui GAO ; Chan CAO ; Yilun YING ; Wei MA ; Yitao LONG
Chinese Journal of Analytical Chemistry 2015;(7):971-976
A novel amplifier system was proposed for low-noise recording of pico-ampere current in nanopore experiment (<100 pA). As an example, the amplifier system was applied in α-hemolysin based nanopore detection of DNA-PEG-DNA conjugate to record the signals of translocation and bumping events in buffer solution (1 mol/L KCl, 10 mmol/L Tris--HCl, 1 mmol/L EDTA and pH=8. 0). The amplified current signal was filtered by a 3 kHz Bessel filter and sampled by a 100 kHz analog-digital convertor. As a result, the presented amplifier system could lower the noise in recording the current. The current blockages (<10 pA) of single molecules with low amplitude were recovered due to the high signal-to-noise ratio.
3.Comparison of the outcome of H-Loop knotless double row technique and suture bridge technique in repairing L-typed rotator cuff tear under arthroscopy
Yitao YANG ; Chenyang MENG ; Yi LONG ; Cheng LI ; Jinming ZHANG ; Jingyi HOU ; Rui YANG
Chinese Journal of Orthopaedics 2024;44(14):970-978
Objective:To compare the clinical efficacy of the H-Loop knotless double-row technique and the suture bridge technique in repairing L-shaped rotator cuff tears under arthroscopy.Methods:A retrospective analysis was performed on 58 patients with L-shaped rotator cuff injuries who underwent arthroscopic repair at Sun Yat-sen Memorial Hospital, Sun Yat-sen University, between January 2019 and December 2021. The H-Loop knotless double-row technique was used in 16 cases (8 males and 8 females, mean age 63.69±8.78 years), while the suture bridge technique was used in 42 cases (24 males and 18 females, mean age 61.02±7.02 years). The American Shoulder and Elbow Surgeons (ASES) score, University of California Los Angeles Shoulder Score (UCLA), Simple Shoulder Test (SST), shoulder range of motion, and muscle strength were evaluated and compared between the two groups one year after surgery.Results:The follow-up period was 12.81±0.98 months for the H-Loop group and 13.29±0.94 months for the suture bridge group. No significant differences were found between the groups in terms of age, sex, dominant hand, preoperative symptom duration, tear shape, tear size, or long head tendon amputation (P>0.05). The operative time was significantly shorter in the H-Loop group 67.50±16.02 minutes compared to the suture bridge group 76.67±13.19 minutes ( t=2.234, P=0.031). Additionally, the number of anchors used was significantly lower in the H-Loop group 2.00±0 compared to the suture bridge group 4.14±0.35 ( t=16.573, P<0.001). The ASES scores increased significantly in both groups: from 57.44±15.91 to 92.00±4.41 in the H-Loop group and from 58.21±16.58 to 87.71±6.19 in the suture bridge group ( F=53.439, P<0.001; F=72.511, P<0.001). Similarly, the UCLA scores improved from 20.63±3.79 to 31.56±3.65 in the H-Loop group and from 20.83±5.78 to 30.36±4.71 in the suture bridge group ( F=57.788, P<0.001; F=50.043, P<0.001). The Constant-Murley scores also showed significant improvement: from 68.50±15.31 to 87.5±8.70 in the H-Loop group and from 66.21±16.51 to 86.33±9.14 in the suture bridge group ( F=6.733, P<0.001; F=30.173, P<0.001). SST scores increased from 6.38±3.76 to 9.06±2.59 in the H-Loop group and from 6.55±3.31 to 9.17±2.45 in the suture bridge group ( F=2.847, P<0.001; F=11.096, P<0.001). The shoulder flexion range of motion increased from 158.75°±21.25° to 178.75°±47.07° in the H-Loop group and from 139.29°±45.12° to 179.76°±3.42° in the suture bridge group ( t=3.814, P=0.002; t=5.877, P<0.001). Shoulder abduction motion increased from 145°±45.46° to 178.75°±3.42° in the H-Loop group and from 135.24°±47.07° to 179.76°±1.54° in the suture bridge group ( t=2.952, P=0.001; t=6.185, P<0.001). Muscle strength improved from 53.36±25.21 N to 73.69±24.09 N in the H-Loop group and from 43.31±24.49 N to 61.8±30.07 N in the suture bridge group ( t=4.916, P<0.001; t=5.623, P<0.001). The ASES score at one year post-surgery was significantly higher in the H-Loop group 92.00±4.41 compared to the suture bridge group 87.71±6.19 ( t=2.529, P=0.014). There were no significant differences in UCLA scores, Constant-Murley scores, SST scores, shoulder motion, or muscle strength between the groups ( P>0.05). Conclusion:The H-Loop technique provides a good early curative effect. Compared to the traditional suture bridge technique, the H-Loop technique offers a higher early postoperative ASES score, shorter operative time, and fewer anchors required.