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find Author "ZHOU Qiang" 11 results
  • TREATMENT OF CERVICOTHORACIC JUNCTION SPINAL LESIONS BY MODIFIED ANTERIOR APPROACH

    Objective To investigate the therapeutic effectof the modified anterior approach in treatment of the patients with cervicothoracic junction spinal lesions. Methods From September 2000 to January 2005, 23 patients (15 males, 8 females) with spinal lesions in the cervicothoracic junction underwent a standard cervical approach, which was combined with apartial median steotomy and transverse steotomy through the synostosis between the manubrium and body of the sternum to expose the lesion adequately. Among thepatients, 3 had fracture, 7 had dislocation, 6 had tuberculosis, and 7 had tumor. The pathologic change regions was as follows: 2 in the C6-T1 segment, 2in the C6-T2 segment, 3 in the C7-T1 segment, 3 in the T3 segment, 8 in the T1 segment, and 5 in the T2egment. The classification of Frankel were as follows: 2 at grade A, 4 at grade B, 7 at grade C, 4 at grade D, and 6 at grade E. All the patients underwent a radical excision of the affected spinal bone, were given a proper tricortical iliac crest and anterior instrumentation to reconstruct the anterior spinal column, followed by immobilization in a brace for 3-6 months. Results The mean followup period was 30 months (range, 1042 months). Bony fusion was obtained in all the patients.One patient died of pulmonary cancer metastasis 10 months after operation. The nerve function of the spinal cord recovered at different degrees (1 at grade A, None at grade B, 2 at grade C, 10 at grade D, 10 at grade E). Conclusion Ourmodified anterior approach can provide a direct and safe access to the lesions in the region.

    Release date:2016-09-01 09:22 Export PDF Favorites Scan
  • CHONDROGENESIS IN VITRO BY EPIPHYSEAL CHONDROCYTES SEEDING INTO THREE-DIMENSIONAL SCAFFOLDS

    Objective To observe the efficiency and biological characteristics in regenerating in vitro tissue-engineered cartilage from epiphyseal chondrocyte-scaffold complex. MethodsThe first passage epiphyseal chondrocytes were collected and mixed with the biological gel-matrix, the chondrocyte-gel fluid wasdropped into the scaffold to form a complex. The complexes were in vitro cultivated. The changes of complexes in morphology and synthesis of collagens type ⅡandtypeⅠ and aggrecan were observed under the gross and the inverted and light microscopes. The sulfate GAG content in complexes was measured by the the modified dimethylmethylene blue method. Results During cultivation, thecomplexes could keep its original shape with the stable homogeneous three-dimensional distribution of chondrocytes,gradually became milk white and translucence with their rigidity increasing. In the 1st week, the chondrocytic lacunae formed in the complexes. After 2 weeks, the complex was gradually reorganized into the mature engineered cartilage with rich collagen typeⅡand aggrecan and typical cartilage histological structure, but with negative immunological staining of collagen typeⅠ. In the 4th week, the engineered cartilage resembled the nature epiphyseal plate in the characteristic of histological structure, and had over 34% of the sulfate GAG content of the natural epiphyseal plate. Conclusion Theepiphyseal chondrocyte-scaffold complex can be reorganized into typical cartilage with the epiphyseallike histological structure, and be fit for repairing the epiphyseal defect. The tissue engineered cartilage cultivated for 1-2 weeks may be a good choice for repairing epiphyseal defect.

    Release date:2016-09-01 09:33 Export PDF Favorites Scan
  • REPAIR OF UPPER TIBIAL EPIPHYSEAL DEFECT WITH ENGINEERED EPIPHYSEAL CARTILAGE IN RABBITS

    OBJECTIVE: To observe the effect of engineered epiphyseal cartilage regenerated in vitro with 3-D scaffold by chondrocytes from epiphyseal plate in repairing the tibial epiphyseal defect, and to explore the methods to promote the confluence between engineered cartilage and epiphyseal plate. METHODS: Chondrocytes were isolated enzymatically from the epiphyseal plates of immature rabbits, and then planted into the tissue culture flasks and cultivated. The first passage chondrocytes were collected and mixed fully with the self-made liquid biological gel at approximately 2.5 x 10(7) cells/ml to form cell-gel fluid. The cell-gel fluid was dropped into the porous calcium polyphosphate fiber/poly-L-lactic acid(CPPf/PLLA)scaffold, and a cell-gel-scaffold complex formed after being solidified. The defect models of 40% upper tibial epiphyseal plate were made in 72 immature rabbits; they were divided into 4 groups: group A(the cell-gel-scaffold complex was transplanted into the defect and the gap filled with chondrocyte-gel fluid), group B (with noncell CPPf/PLLA scaffold), group C(with fat) and group D(with nothing). The changes of roentgenograph, gross and histology were investigated after 2, 4, 6, 8, 12 and 16 weeks of operation. RESULTS: In group A, the typical histological structure of epiphyseal plate derived from the engineered cartilage with a fine integration between host and donor tissues after 2 weeks. The repaired epiphyseal plate had normal histological structure without deformation of tibia after 4 weeks. The early histological change of epiphyseal closure appeared in the repaired area with varus and shortening deformation of the tibia after 8 weeks. The epiphyseal plate was closed in the repaired area with more evident deformation of tibia; the growth function of repaired epiphyseal plate was 43.6% of the normal one. In groups B, C and D, deformation of tibia occurred after 2 weeks; the defect area of epiphyseal plate was completely closed after 4 weeks. The deformation was very severe without growth of the injured epiphyseal plate after 16 weeks, and no significant difference was observed between the three groups. CONCLUSION: Engineered epiphyseal cartilage can repair the epiphyseal defect in the histological structure with partial recovery of the epiphyseal growth capability. Injecting the suspension of fluid chondrocyte-gel into the defects induces a fine integration of host and donor tissues.

    Release date:2016-09-01 09:35 Export PDF Favorites Scan
  • 5 mm surgical margin improves recurrence-free survival in patients with solitary hepatocellular carcinoma: a propensity score matching analysis

    ObjectiveTo explore the influence of 5 mm surgical margin (SM) width on the prognosis of patients with solitary hepatocellular carcinoma (HCC) and the influence of tumor size and microvascular invasion (MVI) on strategic decision of SM width.MethodsThe clinicopathologic data of patients with solitary HCC underwent the surgical resection in the West China Hospital of Sichuan University from January 2014 to September 2015 were collected. According to the inclusion and exclusion criteria of this study, the prognostic differences of the patients with SM≤5 mm and SM>5 mm were compared after the propensity score matching (PSM), and the influences of the 5 mm SM on the recurrence-free survival rate of large HCC (>5 cm) or small HCC (≤5 cm) and MVI positive or negative patients were analyzed.ResultsA total of 266 eligible patients were included, with a median overall survival of 40.01 months and a median recurrence-free survival of 37.01 months. During the follow-up period, 137 patients recurred and 75 patients died. After PSM, the basic indexes had no significant differences between the patients with SM>5 mm (n=78) and SM≤5 mm (n=78). The results of the multivariate Cox regression analysis showed that the tumor size and MVI were the important factors of the recurrence-free survival (P<0.05) and the tumor size, MVI, HBeAg, and alpha-fetoprotein (AFP) were the important factors of the overall survival (P<0.05) before the PSM; while the MVI and SM were the important factors of the recurrence-free survival (P<0.05), the gender, AFP, and MVI were the important factors of the overall survival (P<0.05) after the PSM. The recurrence-free survival rate of the patients with SM >5 mm had better than that with SM≤5 mm after the PSM, but the overall survival had no difference. In the MVI negative and large HCC subgroups, the patients with SM>5 mm showed the better recurrence-free survival rate. However, in the MVI positive and small HCC subgroups did not show any differences in the recurrence-free survival rate for the different SM widths.ConclusionsAccording to the results of this study, a wider SM (>5 mm) could improve recurrence-free survival in patients with a single tumor within BCLC stage 0/A. For patients without MVI or large HCC, SM>5 mm might be adequate. However, for patients with MVI or small HCC, the determination of an appropriate SM width needs further to be investigated.

    Release date:2020-06-04 02:30 Export PDF Favorites Scan
  • Clinical characteristics and prognosis of cerebral hemorrhage in young and elderly patients

    ObjectiveTo investigate the clinical characteristics and prognosis of cerebral hemorrhage in young and elderly patients, to provide evidences for individual clinical diagnosis and treatment, and lay a foundation for building a predictive model of prognosis in cerebral hemorrhage.MethodsPatients with spontaneous cerebral hemorrhage in the Third People’s Hospital of Chengdu were recruited prospectively and continuously from January 2014 to January 2019. They were divided into the youth group (≤50 years old) and the elderly group (>50 years old), and their risk factors, disease characteristics, etiology, and prognosis were analyzed.ResultsA total of 757 patients were recruited. There were 160 cases (21.1%) in the youth group, including 120 males and 40 females, aged from 17 to 50 years, with an average age of (42.06±7.62) years old; 597 cases (78.9%) in the elderly group, including 361 males and 236 females, aged from 51 to 96 years, with an average age of (69.34±10.56) years old. The incidences of hypertension (74.2% vs. 51.2%), diabetes (15.1% vs. 4.4%), coronary heart disease (12.1% vs. 1.3%), and the level of blood glucose at admission [7.1 (5.8, 8.4) vs. 6.3 (5.3, 8.1) mmol/L] in the elderly group were higher than those in the youth group (P<0.05), respectively. However, the proportions of males (60.5% vs. 75.0%), smoking (24.5% vs. 36.9%), and the diastolic blood pressure at admission [(92.37±18.50) vs. (100.95±25.25) mm Hg (1 mm Hg=0.133 kPa)] in the elderly group were lower than those in the youth group (P<0.05), respectively. There was no significant difference between the two groups in systolic blood pressure at admission, Glasgow Coma Score, National Institutes of Health Stroke Scale score, initial hematoma volume, hematoma enlargement, brain hernia, location of hemorrhage, midline shift, hydrocephalus, combined subarachnoid hemorrhage, or intraventricular extension (P>0.05). Hypertension was the most common etiology in the two groups. There was a significant difference in the etiology of cerebral hemorrhage between the two groups (P<0.05), the difference was mainly reflected in cerebral amyloid angiopathy, cavernous hemangioma, and arteriovenous malformation. The fatality rate during hospitalization (9.4% vs. 20.9%), 3 months after discharge (10.3% vs. 26.3%), and at 1 year follow-up (19.0% vs. 37.6%) in the youth group was lower than that in the elderly group (P<0.05), respectively. The disability rate 3 months after discharge and at 1 year follow-up in the youth group was lower than that in the elderly group (32.1% vs. 44.2%, 16.9% vs. 34.4%; P<0.05), respectively.ConclusionsThe education of healthy lifestyles should be strengthened to reduce the adverse effects of smoking in young patients. Young patients should choose antihypertensives that can control diastolic blood pressure better. There are more structural abnormalities in young patients, so routine vascular examination is reasonable. It is necessary to focus on whether the original underlying diseases are stable in elderly patients. Cerebral amyloid angiopathy is an important cause of cerebral hemorrhage in elderly patients, and is a risk factor of recurrence. Anticoagulation or antiplatelet therapy should be cautious.

    Release date:2021-07-22 06:28 Export PDF Favorites Scan
  • Single-channel electroencephalogram signal used for sleep state recognition based on one-dimensional width kernel convolutional neural networks and long-short-term memory networks

    Aiming at the problem that the unbalanced distribution of data in sleep electroencephalogram(EEG) signals and poor comfort in the process of polysomnography information collection will reduce the model's classification ability, this paper proposed a sleep state recognition method using single-channel EEG signals (WKCNN-LSTM) based on one-dimensional width kernel convolutional neural networks(WKCNN) and long-short-term memory networks (LSTM). Firstly, the wavelet denoising and synthetic minority over-sampling technique-Tomek link (SMOTE-Tomek) algorithm were used to preprocess the original sleep EEG signals. Secondly, one-dimensional sleep EEG signals were used as the input of the model, and WKCNN was used to extract frequency-domain features and suppress high-frequency noise. Then, the LSTM layer was used to learn the time-domain features. Finally, normalized exponential function was used on the full connection layer to realize sleep state. The experimental results showed that the classification accuracy of the one-dimensional WKCNN-LSTM model was 91.80% in this paper, which was better than that of similar studies in recent years, and the model had good generalization ability. This study improved classification accuracy of single-channel sleep EEG signals that can be easily utilized in portable sleep monitoring devices.

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  • Automatic sleep staging algorithm for stochastic depth residual networks based on transfer learning

    The existing automatic sleep staging algorithms have the problems of too many model parameters and long training time, which in turn results in poor sleep staging efficiency. Using a single channel electroencephalogram (EEG) signal, this paper proposed an automatic sleep staging algorithm for stochastic depth residual networks based on transfer learning (TL-SDResNet). Firstly, a total of 30 single-channel (Fpz-Cz) EEG signals from 16 individuals were selected, and after preserving the effective sleep segments, the raw EEG signals were pre-processed using Butterworth filter and continuous wavelet transform to obtain two-dimensional images containing its time-frequency joint features as the input data for the staging model. Then, a ResNet50 pre-trained model trained on a publicly available dataset, the sleep database extension stored in European data format (Sleep-EDFx) was constructed, using a stochastic depth strategy and modifying the output layer to optimize the model structure. Finally, transfer learning was applied to the human sleep process throughout the night. The algorithm in this paper achieved a model staging accuracy of 87.95% after conducting several experiments. Experiments show that TL-SDResNet50 can accomplish fast training of a small amount of EEG data, and the overall effect is better than other staging algorithms and classical algorithms in recent years, which has certain practical value.

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  • Short- and long-term outcomes of pediatric heart transplantation: A retrospective study in a single center

    ObjectiveTo analyze the short- and long-term therapeutic effects of heart transplantation in children. MethodsA retrospective study was conducted on recipients and donors who underwent heart transplantation at the 7th People’s Hospital of Zhengzhou from May 2018 to August 2023, analyzing their clinical characteristics, surgical data, postoperative complications, and survival rates. ResultsA total of 22 children underwent heart transplantation, including 14 males and 8 females, with a median age of 13.5 years and a median weight of 41.9 kg. The primary diseases included: dilated cardiomyopathy in 16 patients, hypertrophic cardiomyopathy in 1 patient, myocardial dysplasia in 3 patients, right ventricular dysplasia in 1 patient, and congenital heart disease with abnormal coronary artery origin in 1 patient. The median age of the donors was 21.0 years, and the median weight was 50.5 kg. The blood types of the donors and recipients were the same, with type A in 10 patients, type B in 5 patients, type O in 5 patients, and type AB in 2 patients. Before transplantation, all children had a New York Heart Association cardiac function grade Ⅳ, with 1 patient assisted by intra-aortic balloon pump (IABP), 3 patients assisted by extracorporeal membrane oxygenation (ECMO), 2 patients assisted by continuous renal replacement therapy (CRRT), and 2 patients on mechanical ventilation. Nine patients met the criteria for emergency child status allocation, and the panel reactive antibody level in the patients was<10%. The median cold ischemic time of the donor heart was 355.0 min, the median aortic cross-clamping time was 45.0 min, the median mechanical ventilation time was 22.5 h, the median postoperative hospital stay was 29.5 d, and the median intensive care unit stay was 6.0 d. After surgery, 4 patients were assisted by ECMO, 2 patients by CRRT, and 7 patients developed complications, including lung fungal infection in 6 patients, liver and kidney dysfunction in 1 patient, local wound non-union and mediastinal infection in 1 patient, and multiple organ failure in 1 patient. Kaplan-Meier curve analysis showed that the survival rates of children after surgery were 91.3% at 1 year and 3 years; the survival rates of adult heart transplant recipients at our center were 86.7% and 73.8% at 1 year and 3 years, respectively, indicating that the survival rate of children with heart transplantation was higher than that of adult patients. ConclusionHeart transplantation is an effective treatment for end-stage heart failure in children, and the short- and long-term survival rates of children with heart transplantation are superior to those of adults. There are still many difficulties to be solved in pediatric heart transplantation, requiring joint efforts from society and the medical community.

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  • The Experimental Study on Healing of Large Segmental Defects by Tissue Engineering Bone in a Goat Model

    目的 研究组织工程骨结合带锁髓内钉修复成年山羊大段负重骨缺损的可行性,探索更可行的技术路径。 方法 将24只成年山羊,通过骨髓穿刺法获取山羊骨髓间充质干细胞(BMSC),将体外扩增及成骨定向诱导的第2代BMSC与同种异体脱钙骨基质(DBM)通过双相接种法构建组织工程骨。24只成年山羊,以带锁髓内钉构建股骨中段3 cm骨缺损模型。随机分为3组,每组8只。实验组以组织工程骨修复骨缺损,对照组单独使用DBM和空白组旷置。术后1、12、24周行X线片观察及评分,12、24周每组各处死4只动物行组织学观察和生物力学检测。 结果 标本大体观察示实验组和对照组术后12周骨缺损部位被骨痂连接,髓腔贯通,24周全部愈合;实验组24周恢复正常解剖形态,对照组外形仍然粗糙、不规则;空白组术后12周及24周缺损部位均为纤维组织充填。术后1周各组X线评分无明显差异(P>0.05),实验组术后12周及24周X线评分均优于对照组和空白组,对照组优于空白组,各组24周X线评分均高于12周时,差异均有统计学意义(P<0.05)。实验组术后12、24周的最大抗扭强度分别达正常侧的47.07% ± 5.05%和83.73% ± 2.33%,显著高于对照组和空白组(P<0.05);空白组2个时间点最大抗扭强度均不超过正常的15%,与骨不连时的纤维连接相符。组织学检查示术后12周实验组和对照组骨缺损区DBM支架材料基本被吸收,有典型的同心圆排列的哈弗系统形成,周围偶见淋巴细胞;术后24周,实验组和对照组股骨缺损均被修复,但实验组较对照组的新骨更多、骨塑形更好;空白组术后24周骨缺损区中央仍为纤维组织填充。 结论 组织工程骨结合带锁髓内钉能够更有效修复成年山羊负重骨大段骨缺损,满足负重骨的生物力学要求。

    Release date:2016-09-08 09:12 Export PDF Favorites Scan
  • Transfection of lentivirus-bone morphogenetic protein 2 and lentivirus-inhibitor of differentiation 1 into nucleus pulposus for delaying intervertebral disc degeneration in anin vivo rabbit model

    Objective To investigate if the course of intervertebral disc degeneration (IDD) is delayed by injecting lentivirus (Lv) vector carrying bone morphogenetic protein 2 (BMP-2) and inhibitor of differentiation 1 (Id1) genes directly into the nucleus pulposus. Methods Thirty-two New Zealand white rabbits, 2.0-2.5 kg in weight and 4 months in age, were used to establish the IDD models at L3, 4, L4, 5, and L5, 6 discs with annular puncture via transabdominal approach. Thirty rabbits with successful modeling were randomly divided into 5 groups, 6 rabbits every group. At 4 weeks after modeling, rabbits were injected with Lv-BMP-2 (group A), with Lv-BMP-2 and Lv-Id1 (group B), with Lv-Id1 (group C), with Lv-green fluorescent protein (group D), and with PBS (group E). At 2, 4, and 8 weeks after injection, T2-mapping MRI was performed on 2 rabbits each group to obtain the T2 values, and then subsequently the lumbar disc tissues were harvested to test the mRNA expressions and contents of collagen type II and proteoglycan by real-time fluorescent quantitative PCR and ELISA methods. Results T2-mapping MRI demonstrated that there was no significant difference in the T2 value between different groups at immediate and 2 weeks after injection (P>0.05). The T2 value of groups A and B was significantly higher than that of groups C, D, and E at 4 weeks after injection (P<0.05), but no significant difference was observed between group A and group B (P>0.05). The T2 value of group B was significantly higher than that of the other groups at 8 weeks after injection (P<0.05). The real-time fluorescent quantitative PCR and ELISA showed that the expressions and contents of collagen type II and proteoglycan in group B were significantly higher than those in the other groups at 2, 4, and 8 weeks after injection (P<0.05). Conclusion Combined application of Lv-BMP-2 and Lv-Id1 can delay IDD changes in rabbit IDD models.

    Release date:2017-02-15 09:26 Export PDF Favorites Scan
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