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find Author "XU Yan" 20 results
  • Primary Study on Anatomical Extent of Lymph Node Metastases in Gastric Cancer and Its Significance in Surgical Treatment

    Objective To evaluate the status of lymph node metastasis and reasonable procedure in gastric cancer. Methods The incidence of metastases from gastric cancer to various regional lymph node stations was studied in 1 505 patients with gastric cancer. The patients underwent surgical resection from January 1995 to December 2004.Results Lymph node metastasis were observed in 928 of 1 505 cases (61.7%). Lymph node metastasis frequency was found in groups No.1 (32.9%),No.3 (28.7%), No.2 (20.4%), and No.7 (18.6%) at upper third stomach cancer;in groups No.3 (32.5%), No.4 (24.7%), No.7 (20.6%), and No.1 (17.3%) at middle third stomach cancer; in groups No.6 (33.7%), No.3 (31.3%), No.4 (25.6%), and No.7 (21.5%) at lower third stomach cancer. Conclusions Distribution of metastatic lymph node is clearly related to the location of the tumor. Anatomical extent of lymph node metastases in gastric cancer provid surgical guidance for surgeons.

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  • EFFECTS OF PERIOSTEUM, SYNOVIUM AND CARTILAGE TISSUES ON GENES FOR JOINT CARTILAGE REGENERATION

    Objective To study the effects of the periosteum,synovium andcartilage tissues on the gene expressions of proteoglycan, collagen Ⅱ, andnuclear factor kappa B (NF-κB) and to investigate the different effects of these tissues on cartilage regeneration. Methods In 20 New Zealand white rabbits, 20 cartilage explants were taken from the knee joints in each rabbit, the sizeof which was 4 mm×4 mm×4 mm. All the cartilages were divided into the following 4 groups and cultured for 7 days: Group A, with 5 pieces (2 mm×2 mm) of the synovium of theknee joints in each dish; Group B, with 5 pieces (2 mm×2 mm) of the periosteum ineach dish; Group C, with 5 pieces (2 mm×2 mm×2 mm) of the cartilage in each dish; and Group D, with no addition of other tissues (control group). RNA was extracted from the cells of the cartilage explants (4 mm×4 mm×4 mm) in all the dishes. Thegene expressions of proteoglycan, collagen Ⅱ and NF-κB were defected by a reversetranscription-polymerase chain reaction (RT-PCR).Results In group A, the gene expression of proteoglycan was significantly decreased. The relative density of this gene expression had a significant difference when compared with that in group D (1.09±0.21 vs. 1.25±0.25, Plt;0.05); the gene expressions of collagen Ⅱ and NF-κB were also decreased, but they had no significant differences when compared with those in group D (Pgt;0.05). In groupB, the gene expressions of proteoglycan, collagen Ⅱ, and NF-κB were significantly increased. The relative densities of these gene expressions were 1.60±0.26, 1.57±0.24, and 4.20±2.22, respectively, which had significant differences when compared with those in group D (Plt;0.05). In group C, the relative density of the gene expression of collagen Ⅱ was 1.43±0.28, which had a significant difference when compared with that in group D (Plt;0.05), but therelative densities of the gene expressions of proteoglycan and NF-κB had no significant differences when compared with those in group D (Pgt;0.05). Conclusion The results indicate that the periosteum can up-regulate the gene expressions of proteoglycan, collagen Ⅱ and NF-κB. The NF-κB is likely to be an important nuclear transcription factor related to cartilage regeneration. The results also suggest that the periosteum maybe better in facilitating the cartilage repair and regeneration in clinical practice.

    Release date:2016-09-01 09:26 Export PDF Favorites Scan
  • Key issues and strategies in the construction of biobank

    Biobank is an important platform for translational medicine, precision medicine and drug development. In the past 10 years, although the construction of biobank in China has made great progress, it still faces many challenges. This article analyzes the key issues and also puts forward specific suggestions in the management of biobank from the aspects of ethics issues, quality control of biospecimens, information management, sample and data sharing, so as to provide reference for the construction and development of a high standard biobank.

    Release date:2018-06-26 08:57 Export PDF Favorites Scan
  • Automated detection of sleep-arousal using multi-scale convolution and self-attention mechanism

    In clinical, manually scoring by technician is the major method for sleep arousal detection. This method is time-consuming and subjective. This study aimed to achieve an end-to-end sleep-arousal events detection by constructing a convolutional neural network based on multi-scale convolutional layers and self-attention mechanism, and using 1 min single-channel electroencephalogram (EEG) signals as its input. Compared with the performance of the baseline model, the results of the proposed method showed that the mean area under the precision-recall curve and area under the receiver operating characteristic were both improved by 7%. Furthermore, we also compared the effects of single modality and multi-modality on the performance of the proposed model. The results revealed the power of single-channel EEG signals in automatic sleep arousal detection. However, the simple combination of multi-modality signals may be counterproductive to the improvement of model performance. Finally, we also explored the scalability of the proposed model and transferred the model into the automated sleep staging task in the same dataset. The average accuracy of 73% also suggested the power of the proposed method in task transferring. This study provides a potential solution for the development of portable sleep monitoring and paves a way for the automatic sleep data analysis using the transfer learning method.

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  • AN EXPERIMENTAL OSTEONECROSIS OF FEMORAL HEAD INDUCED BY A COMBINATION OF A SINGLELOW-DOSE LIPOPOLYSACCHARIDE AND METHYLPREDNISONE

    【Abstract】 Objective To investigate both incidence and mechanism attributing to steroid-associated osteonecrosisof femoral head(ONFH) using an experimental protocol with a single low-dose l i popolysaccharide (LPS) injection andsubsequently three injections of high-dose methylprednisolone (MPS). Methods Twenty-five New Zealand white rabbits with body weight of (3.0 ± 0.3) kg were divided randomly into 2 groups. In treatment group, 19 rabbits received one intravenous injection of LPS (10 μg/kg); 24 hours later, three injections of 20 mg/kg of MPS were given intramuscularly at an interval of 24 hours. Additional 6 rabbits which received normal sal ine injection at the same time point were used as controls(control group). The blood samples were collected for hematological examinations before and after LPS injection, MRI was performed on bilateral hip six weeks after last MPS injection, meanwhile, bone marrow was aspirated from femoral head region to evaluate stem cell’s activity. Bilateral femoral heads were harvested to make histopathology examination. Results All animals survived throughout the experiment period except one death on the second day after LPS injection. In the histopathological examinationfor the femoral head, ONFH+ was observed in 16 rabbits (88.9%), and the lesions were mainly in the metaphysis. In ONFH+ rabbits, micro vessels fibrous thrombosis and extravascular marrow fat cell size increasing were found around necrotic bone; The femoral heads of control group had no changes. MRI accurate ratio was 93.8% (15/16). Compared to basel ine, a significant decrease in ratio of tissue plasminogen activator/plasminogen activator inhibitor 1 and activated partial thromboplatin time, and a significant increase in ratio of low-density l ipoprotein/high-density l ipoprotein were only found in ONFH+ rabbits (P lt; 0.05). Meanwhile there was a significant decrease in the number of CFU-F (8.50 ± 9.63) compared with the control (70.17 ± 7.78, P lt; 0.05). Conclusion A single low-dose LPS injection and subsequent three injections of high-dose MPS is effective on building steroid-associated ONFH model, coagulation and l ipometabol ism abnormal ity, activity degeneration of stem cell may be the key factors of ONFH.

    Release date:2016-09-01 09:10 Export PDF Favorites Scan
  • AN EXPERIMENTAL STUDY ON TREATMENT OF STEROID-ASSOCIATED FEMORAL HEAD NECROSIS WITHSIMVASTATIN AND BMSCs TRANSPLANTATION

    【Abstract】 Objective To approach the possibil ity of combination of simvastatin and BMSCs transplantation forsteroid-associated osteonecrosis of femoral head. Methods The BMSCs harvested from 24 rabbits were prepared for cell suspension at a concentration of 1 × 107/mL, and combined with gelatin sponge. Seventy New Zealand white rabbits received one intravenous injection of l ipopolysaccharide (10 μg/ kg). After 24 hours, three injections of 20 mg/kg of methylprednisolone were given intramuscularly at a time interval of 24 hours. Forty-eight rabbits diagnosed as having femoral head necrosis by MRI were divided into 4 groups randomly, group A: no treatment; group B: only decompression; group C: decompression and BMSCs transplantation; and group D: simvastatin drench (10 mg/kg.d) decompression and BMSCs transplantation. The general information of animals were recorded; after 4 and 8 weeks of operation, 6 rabbits of each group were chosen randomly to do MRI scan, and femoral heads were harvested to do histopathology and scanning electron microscope examination. Results After 8 weeks, rabbits became more active than before treatment, and walking way became normal gradually in groups C and D. Fourweeks after operation, the MRI low signal region of all groups had no obvious changes, but 8 weeks later, the necrosis signal region of group A magnified while it reduced obviously in group D. Histopathological observation: 4 weeks after operation, diffuse presence of empty lacunae and pyknotic nuclei of osteocytes were found in the trabeculae, and few newborn micrangium could been seen in group A; lots of empty lacunae and a small quantity of newborn micrangium could been found in group B; and large amounts of osteoblats and newborn micrangium were found around the necrosis regions in groups C and D. The positive ratio of empty lacunae and microvessel density in group D were 19.30 ± 1.52 and 7.08 ± 1.09, showing significant difference compared with other groups (P lt; 0.05). After 8 weeks of treatment, the bone trabecula collapsed in many regions in group A; there was fibra callus formation along the decompression channel in group B; few empty lacunae was in the bone trabecular, but the shape of marrow cavity was not normal in group C; and it showed almost normal appearance in group D. The positive ratio of empty lacunae and microvessel density in group D were 11.31 ± 1.28 and 12.37 ± 1.32, showing significant differences compared with other groups (P lt; 0.05), meanwhile, showing significant difference compared with that of 4 weeks after operation(P lt; 0.05). Scanning electron microscope: 8 weeks after operation, the bone trabecula collapsed in many regions, and few osteoblasts could be found on the surface, a great quantity of fat cells cumulated in the bone marrow in group A; cracked bone trabecula could be found occasionally in group B; the density of bone trabecula was lower than the normal in group C; and the shape of the marrow avity and thedensity of bone trabecula were similar to the normal in group D. Conclusion Simvastatin can promote the differentiation of osteocyte and vascular endothel ial cell from MSCs, the combination of simvastatin and marrow stem cells transplantation for the treatment of steroid-associated osteonecrosis of femoral head have good appl ication prospects.

    Release date:2016-09-01 09:10 Export PDF Favorites Scan
  • Anti-interference hemoglobin analysis system by high performance liquid chromatography

    High performance liquid chromatography (HPLC) is currently the mainstream technology for detecting hemoglobin. Glycated hemoglobin (HbA1c) is a gold indicator for diagnosing diabetes, however, the accuracy of HbA1c test is affected by thalassemia factor hemoglobin F (HbF)/hemoglobin A2 (HbA2) and variant hemoglobin during HPLC analysis. In this study, a new anti-interference hemoglobin analysis system of HPLC is proposed. In this system, the high-pressure three-gradient elution method was improved, and the particle size and sieve plate aperture in the high-pressure chromatography column and the structure of the double-plunger reciprocating series high-pressure pump were optimized. The system could diagnose both HbA1c and thalassemia factor HbF/HbA2 and variant hemoglobin, and the performance of the system was anti-interference and stable. It is expected to achieve industrialization. In this study, the HbA1c and thalassemia factor HbF/HbA2 detection performance was compared between this system and the world’s first-line brand products such as Tosoh G8, Bio-Rad Ⅶ and D10 glycosylated hemoglobin analysis system. The results showed that the linear correlation between this system and the world-class system was good. The system is the first domestic hemoglobin analysis system by HPLC for screening of HbA1c and thalassemia factor HbF/HbA2 rapidly and accurately.

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  • Incidence of skin adverse reactions in patients with lung cancer treated by immunotherapy: a meta-analysis

    ObjectiveTo systematically review the incidence of adverse skin reactions in lung cancer patients treated by immunotherapy. MethodsPubMed, Web of Science, The Cochrane Library, CNKI, WanFang Data and VIP databases were electronically searched to collect the studies on the incidence of skin adverse reactions in lung cancer patients treated with immunotherapy from June 2011 to June 2021. Two reviewers independently screened literature, extracted data and assessed the risk bias of the included studies. Meta-analysis was then performed by using Stata 15.0 software. ResultsA total of 63 studies were included, with a total sample size of 13 386 cases. The results of meta-analysis showed that the overall incidence of adverse skin reactions in lung cancer patients was 14.0% (95%CI 11.6% to 16.5%). ConclusionCurrent evidence shows that the incidence of adverse skin reactions in lung cancer patients with immunotherapy is high. Due to the limited quality and quantity of the included studies, more high-quality studies are needed to verify the above conclusions.

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  • Application effect of early enteral nutrition support based on enhanced recovery after surgery in perioperative period of children with perforated appendicitis

    ObjectiveTo investigate the effect of early enteral nutrition (EEN) support in the perioperative period of children with perforated appendicitis based on the enhanced recovery after surgery (ERAS). MethodsThe children with perforated appendicitis were collected as an observation group, who underwent EEN support treatment based on the ERAS mode from January 2021 to December 2022 in the Xuzhou Children’s Hospital. At the same time, the children with perforated appendicitis received conventional nutrition support from January 2019 to December 2020 were matched as a control group according to the principle of balanced and comparable baseline data such as the gender, age, disease course, pathological type, and body mass index with the observation group. The time of first exhaust or defecation and the hospital stay after surgery were compared. Meanwhile, the nutritional indexes [prealbumin (PA), albumin (ALB), hemoglobin (Hb)], immune indexes [immunoglobulin (Ig) A, IgM, IgG], serum inflammatory factors [C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)] before surgery, on day 1 and 7 after surgery were compared. And the adverse effects were observed. ResultsThere were 40 children with perforated appendicitis in the observation group and the control group, respectively. There were no statistical differences in the baseline data such as the gender, age, course of disease, pathological type, and body mass index between the two groups (P>0.05). The time of first exhaust or defecation and the hospital stay after surgery in the observation group were shorter than in the control group (t=3.234, P=0.002; t=5.582, P<0.001). The levels of PA, ALB, Hb, IgA, IgM, and IgG in the observation group were higher than in the control group on day 7 after surgery (P<0.05). The levels of CRP, IL-6, and TNF-α in the observation group were lower than in the control group on day 7 after surgery (P<0.05). The incidence of adverse reactions in the observation group was lower than that in the control group [5.0% (2/40) vs. 22.5% (9/40), χ2=5.165, P=0.023]. ConclusionsFrom on the results of this study, EEN support based on ERAS during perioperative period of children with perforated appendicitis contributes to recover gastrointestinal function, correct nutritional status, improve immune function, and reduce inflammation, and which has a higher safety for children with perforated appendicitis.

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  • EFFECT OF BONE MARROW MESENCHYMAL STEM CELLS-DERIVED EXTRACELLULAR MATRIX SCAFFOLD ON CHONDROGENIC DIFFERENTIATION OF MARROW CLOT AFTER MICROFRACTURE OF BONE MARROW STIMULATION IN VITRO

    Objective To evaluate the feasibility and validity of chondrogenic differentiation of marrow clot after microfracture of bone marrow stimulation combined with bone marrow mesenchymal stem cells (BMSCs)-derived extracellular matrix (ECM) scaffold in vitro. Methods BMSCs were obtained and isolated from 20 New Zealand white rabbits (5-6 months old). The 3rd passage cells were cultured and induced to osteoblasts, chondrocytes, and adipocytes in vitro, respectively. ECM scaffold was manufactured using the 3rd passage cells via a freeze-dying method. Microstructure was observed by scanning electron microscope (SEM). A full-thickness cartilage defect (6 mm in diameter) was established and 5 microholes (1 mm in diameter and 3 mm in depth) were created with a syringe needle in the trochlear groove of the femur of rabbits to get the marrow clots. Another 20 rabbits which were not punctured were randomly divided into groups A (n=10) and B (n=10): culture of the marrow clot alone (group A) and culture of the marrow clot with transforming growth factor β3 (TGF-β3) (group B). Twenty rabbits which were punctured were randomly divided into groups C (n=10) and D (n=10): culture of the ECM scaffold and marrow clot composite (group C) and culture of the ECM scaffold and marrow clot composite with TGF-β3 (group D). The cultured tissues were observed and evaluated by gross morphology, histology, immunohistochemistry, and biochemical composition at 1, 2, 4, and 8 weeks after culture. Results Cells were successfully induced into osteoblasts, chondrocytes, and adipocytes in vitro. Highly porous microstructure of the ECM scaffold was observed by SEM. The cultured tissue gradually reduced in size with time and disappeared at 8 weeks in group A. Soft and loose structure developed in group C during culturing. Chondroid tissue with smooth surface developed in groups B and D with time. The cultured tissue size of groups C and D were significantly larger than that of group B at 4 and 8 weeks (P lt; 0.05); group D was significantly larger than group C in size (P lt; 0.05). Few cells were seen, and no glycosaminoglycan (GAG) and collagen type II accumulated in groups A and C; many cartilage lacunas containing cells were observed and more GAG and collagen type II were synthesized in groups B and D. The contents of GAG and collagen increased gradually with time in groups B and D, especially in group D, and significant difference was found between groups B and D at 4 and 8 weeks (P lt; 0.05). Conclusion The BMSCs-derived ECM scaffold combined with the marrow clot after microfracture of bone marrow stimulation is effective in TGF-β3-induced chondrogenic differentiation in vitro.

    Release date:2016-08-31 04:07 Export PDF Favorites Scan
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