Objective To investigate the effect of dynamic compression and rotation motion on chondrogenesis of the 3rd passage cell-loaded three-dimensional scaffold in a joint-specific bioreactor in vitro so as to provide theoretical basis of the autologous chondrocyte transplantation in clinical practice. Methods Primary chondrocytes were isolated and cultured from the knee cartilage of 3-4 months old calves. The 3rd passage cells were seeded onto fibrin-polyurethane scaffolds (8 mm × 4 mm). Experiment included 5 groups: unloaded culture for 2 weeks (group A), direct load for 2 weeks (group B), unloaded culture for 4 weeks (group C), direct load for 4 weeks (group D), and unload for 2 weeks followed by load for 2 weeks (group E). The cell-scaffold was incubated in incubator (unload) or in a joint-specific bioreactor (load culture). At different time points, the samples were collected for DNA and glycosaminoglycan (GAG) quantification detect; mRNA expressions of chondrogenic marker genes such as collagen type I, collagen type II, Aggrecan, cartilage oligomeric matrix protein (COMP), and superficial zone protein (SZP) were detected by real-time quantitative PCR; and histology observations were done by toluidine blue staining and immunohistochemistry staining. Results No significant difference was found in DNA content, GAG content, and the ratio of GAG to DNA among 5 groups (P gt; 0.05). After load, there was a large number of GAG in the medium, and the GAG significantly increased with time (P lt; 0.05). The mRNA expression of collagen type I showed no significant difference among 5 groups (P gt; 0.05). The mRNA expression of collagen type II in group B was significantly increased when compared with group A (P lt; 0.01), and groups D and E were significantly higher than group C (P lt; 0.01); the mRNA expression of Aggrecan in groups D and E were significantly increased when compared with group C (P lt; 0.01), and group E was significantly higher than group D (P lt; 0.01); the mRNA expression of COMP in group B was significantly increased when compared with group A (P lt; 0.01), and group E was significantly higher than group C (P lt; 0.01); and the mRNA expression of SZP in group E was significantly increased when compared with groups C and D (P lt; 0.05). The toluidine blue staining and immunohistochemistry staining displayed that synthesis and secretion of GAG could be enhanced after load; no intensity changes of collagen type I and collagen type II were observed, but intensity enhancement of Agrrecan was seen in groups D and E. Conclusion Different dynamic loads can promote chondrogenesis of the 3rd passage chondrocytes. Culture by load after unload may be the best culture for chondrogenesis, while the 3rd passage chondrocytes induced by mechanical load hold less capacity of chondrogenesis.
Objective To explore a better method in obtaining iris pigment epithelium(IPE) specimen for autologous transplantation in rabbits． Methods IPE was obtained from 20 black rabbits with method A，i.e.surgical peripheral iridectomy at 12:00 position obtaining a triangle iris tissue with the hemline of 4-5 mm in left eyes，and method B,i.e.surgical peripheral iridectomy at 11:00 and 1:00 positions obtaining two triangle iris tissues with the hemlines of 2-2.5 mm in right eyes . The IP E cells were isolated precisely with enzyme microdissection-enzyme isolation method, cultured in vitro, observed with light and electronic microscope, and ident ified with immunocytochemical staining.ResultsThe success ra te of cells culture were 65% for method A and 95% for method B. After 3-4 generations of culturing，the amount of IPE cells was enough for transplantation, and most of the functions of primary clutured IPE cells were kept still. Viability of IPE cells was 85%-93%. Conclusion The success rate of cells culture for method B is higher than that for method A. The third generation of cultured cells is available for autologous transplantation.(Chin J Ocul Fundus Dis，2003，19：201-268)
Objective To analyze the learning curve of unilateral biportal endoscopic lumbar interbody fusion (UBE-LIF). Methods Fifty-five patients with single-segment lumbar degenerative disease treated with UBE-LIF between December 2020 and February 2022 were selected as the research subjects. The patients were grouped according to the operation sequence, the first 27 cases were in the early group, and the last 28 cases were in the late group. There was no significant difference between the two groups in age, gender, disease type, and surgical segment distribution (P>0.05). The operation time, the amount of hemoglobin loss (the difference between 1 day before operation and 3 days after operation), the hospital stay after operation, and the incidence of perioperative complications were recorded; the learning curve of UBE-LIF was analyzed by log-curve regression analysis. Results All the operations were successfully completed without changing to other operations. The operation time, the amount of hemoglobin loss, and hospital stay in the early group were significantly more than those in the late group (P<0.05). Complications occurred in 2 cases (7.4%) in the early group, including 1 case of dural tear during operation and 1 case of epidural hematoma after operation, and 1 case (3.6%) with transient radiculitis in the late group. There was no significant difference in the incidence of complications between the two groups (P=0.518) . The log-curve regression analysis showed that the operation time decreased significantly with the increase of the number of patients (P<0.05). The operation time tended to be stable after the surgeon completed 17 cases. ConclusionFor single-level lumbar degenerative disease, the operation time of UBE-LIF can decrease gradually with the increase of the number of patients, and tend to be stable after 17 cases.
To address the issue of a large number of network parameters and substantial floating-point operations in deep learning networks applied to image segmentation for cardiac magnetic resonance imaging (MRI), this paper proposes a lightweight dilated parallel convolution U-Net (DPU-Net) to decrease the quantity of network parameters and the number of floating-point operations. Additionally, a multi-scale adaptation vector knowledge distillation (MAVKD) training strategy is employed to extract latent knowledge from the teacher network, thereby enhancing the segmentation accuracy of DPU-Net. The proposed network adopts a distinctive way of convolutional channel variation to reduce the number of parameters and combines with residual blocks and dilated convolutions to alleviate the gradient explosion problem and spatial information loss that might be caused by the reduction of parameters. The research findings indicate that this network has achieved considerable improvements in reducing the number of parameters and enhancing the efficiency of floating-point operations. When applying this network to the public dataset of the automatic cardiac diagnosis challenge (ACDC), the dice coefficient reaches 91.26%. The research results validate the effectiveness of the proposed lightweight network and knowledge distillation strategy, providing a reliable lightweighting idea for deep learning in the field of medical image segmentation.
Objective To investigate preoperative blood neutrophil-to-lymphocyte ratio （NLR） in patients with gastrointestinal stromal tumor （GIST） and analyze the relationship of the NLR to prognosis. Methods The data of NLR of peripheral blood samples on 3d before surgery and the results of immunohistochemistry of 42 patients with GIST were analyzed respectively，the relation between the NLR and the prognosis of patients with GIST was understood by the survival analysis. Results The patients with high NLR （NLR≥2.5） was found in 22 cases， low NLR （NLR＜2.5） in 20 cases.The NLR was related to mitotic figures （χ2=9.45，P=0.002） and tumor size （P=0.041）. The 3-year survival rate of the patients with high NLR was shorter than that of the low NLR （χ2=5.44，P=0.022）. The 3-year survival rate was associated with NLR，mitotic figures，and tumor size （P＜0.05） in univariate analysis. The NLR and mitotic figures were independent prognostic indicators of 3-year survival （P=0.018，P=0.000） in Cox multivariate analysis. Conclusion Blood NLR and mitotic figures have some predictive value for the prognosis of patients with GIST.
Repetitive transcranial magnetic stimulation(rTMS) is a painless and non-invasive method for stimulation and modulation in the field of cognitive neuroscience research and clinical neurological regulation. In this paper, adult Wistar rats were divided into the rTMS group and control group randomly. Rats in the rTMS group were stimulated with 5 Hz rTMS for 14 days, while the rats in the control group did not accept any stimulation. Then, the behavior and local field potentials (LFPs) were recorded synchronously when the rats perform a working memory (WM) task with T-maze. Finally, the time-frequency distribution and coherence characteristics of the LFPs signal in the prefrontal cortex (PFC) during working memory task were analyzed. The results showed that the rats in the rTMS group needed less training days to reach the task correction criterion than the control group (P < 0.05). Compared with the control group, the rTMS group has higher energy (P < 0.01) in θ band (4~12 Hz) and γ band (30~80 Hz). The coherence between the channel pairs decreases as the spatial distance of the channel pairs increases, and the rTMS group exhibits a higher coherence than the control group (P < 0.01). It is concluded that 5 Hz rTMS can improve the excitability of rat prefrontal cortical neurons to a certain extent, and has a positive effect on the working memory ability of normal rats. The results of this paper may provide important theoretical support for further research on the mechanism of action of rTMS on WM.
ObjectiveTo summarize the minimally invasive experiences and medium-long-term results of perventricular device closure of ventricular septal defects (VSD) under transesophageal echocardiography (TEE) guidance.MethodsWe retrospectively analyzed the clinical data and medium-long-term follow-up results of 783 patients who undertook perventricular device closure under TEE guidance in Dalian Children’s Hospital from July 2011 to January 2020, in which perimembrane VSD were found in 598 patients, VSD with aortic valve prolapse in 135 patients and muscular VSD in 2 patients. There were 463 males and 320 females at age of 5 months to 13 years with average age of 3.3±1.2 years, and body weight of 5.9-51.0 (15.9±8.3) kg. The left ventricular defect diameter of the VSD ranged from 5.0 to 11.0 mm, with an average of 6.3±1.2 mm. The right ventricular defect diameter of the VSD ranged from 2.3 to 8.0 mm, with an average of 4.3±0.9 mm.ResultsThe procedures were completed successfully in 753 patients. The device of 1 patient (0.1%) fell off and embedded in the right pulmonary artery after the operation, and the occluder was taken out and the VSD was closed with cardiopulmonary bypass (CPB) in the secondary operation. One patient (0.1%) appeared Ⅲ degree atrioventricular block in 2 years after operation. The device was taken out and VSD was closed with CPB in the secondary operation, and the patient gradually reached to sinus rhythm in post-operation. Eight patients (1.1%) presented delayed pericardial effusion in 1 week after operation, and were cured by pericardiocentesis with ultrasound-guided. Symmetric occluders were used in 580 patients, eccentric occleders were used in 171 patients and muscular occluders were used in 2 patients. The follow-up time was 9 months to 9 years. The rate of loss to follow-up was 96.7% (704/728). No residual shunt, occlude-loss or arrhythmia was found during follow-up. Conclusion The minimally invasive penventricular device closure of VSD guided by TEE is safe and availabe. Medium-long-term follow-up results are satisfactory, it is worthy of clinical promotion, and longer term follow-up is still needed.
【Abstract】Objective To study the clinical application of laparoscopic operation. Methods The clinical findings from 13 840 cases of laparoscopic surgery in this hospital from 1992 to 2005 were reviewed retrospectively.Results Laparoscopic operation were performed successfully in 13 653（98.6%）,187 cases were transferred to open operation. Complications were occurred in 115 cases, including common bile duct injury in 3 cases. Combined treatment with laparoscope and endoscope were performed in 162 cases. Eleven thousand three hundred and fiftytwo patients had been succeeded in followup survey. Over 90.0 percent of patients recovered smoothly. Conclusion Laparoscopic operation may be applied in a more extensive scope. The major complications can be reduced by strict procedures of laparoscopic operation. The combined treatment of laparoscope and endoscope should be further studied and widely used.
Objective To evaluate the feasibility of the anterior cruciate ligament (ACL) reconstruction with 6 strands of hamstring tendons enveloped by periosteum. Methods Between April 2008 and April 2009, 34 patients with ACL injury were treated, ACL of whom was reconstructed with 6 strands of hamstring tendons enveloping of periosteum and double Rigidfix fixation. There were 30 males and 4 females, aged 19-54 years with an average of 29.4 years. The causes of injury included sport in 19 cases, traffic accident in 8 cases, falling from height in 5 cases, and other in 2 cases. The locations were left knee in 19 cases and right knee in 15 cases. The disease duration was 3 weeks to 18 months (median, 9.4 months). The results of Lachman test and anterior drawer test were positive. The Lysholm knee score was 61.5 ± 3.6. MRI examination revealed ACL rupture in 26 cases and ACL injury in 8 cases. Results All incisions healed by first intention, and no early complication occurred. Twenty-eight cases were followed up 12-32 months (mean, 16.1 months). The result of Lachman test was negative at 12 months after operation; in all patients, knee extension reached 0°, and flexion reached 120-150° (mean, 132.5°). The AP and lateral X-ray films and MRI showed no bone tunnel expansion. At last follow-up the therapeutic effect evaluation was excellent in 25 cases, good in 1 case, and fair in 2 cases; the excellent and good rate was 92.9%. The postoperative Lysholm score was 91.0 ± 3.2, showing significant difference when compared with preoperative score (t=32.78, P=0.00). Conclusion Six strands of hamstring tendons can ensure sufficient tensile strength, and use of the double Rigidfix absorbable screw makes fixation more reliable. Facing outside suture of periosteal flap can promote tendon-bone healing, so it is a good method of ACL reconstruction.
目的 探讨腹腔镜下胆道镜联合微爆破碎石术仪治疗肝胆管结石的安全性及治疗效果。 方法 回顾分析2008年7月－2012年6月183例胆道结石患者，行腹腔镜下胆道镜联合微爆破碎石仪治疗或单纯经内镜Oddi括约肌切开取石治疗的临床资料。87例患者在术中均应用微爆破碎石仪碎石（微爆破组），96例患者行单纯经内镜Oddi括约肌切开术或经内镜乳头切开术碎石（对照组）。 结果 微爆破组碎石成功率100%，结石取净率85.06%（74/87），微爆破组的碎石时间、平均住院时间、平均住院总费用、并发症发生率均明显低于对照组（P＜0.05）。 结论 腹腔镜下胆道镜联合微爆破碎石术在治疗肝胆管结石病方面，具有微创、安全、经济有效的优点，能降低结石残留率及取石次数，值得临床推广。