Objective: To compare the clinical outcomes and biomechanical characteristics of 1-, 2-, and 3-level pedicle subtraction osteotomy (PSO), and establish selection criteria based on preoperative radiographic parameters. Methods: Patients undergone PSO to treat ankylosing spondylitis from February 2009 to May 2019 in Sun Yat-sen Memorial Hospital of Sun Yat-sen University were enrolled. According to the quantity of osteotomy performed, the participants were divided into group A (1-level PSO, n = 24), group B (2-level PSO, n = 19), and group C (3-level PSO, n = 11). Clinical outcomes were assessed before surgery and at the final follow-up. Comparisons of the radiographic parameters and quality-of-life indicators were performed among and within these groups, and the selection criteria were established by regression. Finite element analysis was conducted to compare the biomechanical characteristics of the spine treated with different quantity of osteotomies under different working conditions. Results: Three-level PSO improved the sagittal parameters more significantly, but resulted in longer operative time and greater blood loss (p < 0.05). Greater stress was found in the proximal screws and proximal junction area of the vertebra in the model simulating 1-level PSO. Larger stress of screws and vertebra was observed at the distal end in the model simulating 3-level PSO. Conclusion Multilevel PSO works better for larger deformity correction than single-level PSO by allowing greater sagittal parameter correction and obtaining a better distribution of stress in the hardware construct, although with longer operation time and greater blood loss. Three-level osteotomy is recommended for the patients with preoperative of global kyphosis > 85.95°, T1 pelvic angle > 62.3°, sagittal vertical alignment > 299.55 mm, and pelvic tilt+ chin-brow vertical angle > 109.6°.

Objective: To compare the clinical outcomes and biomechanical characteristics of 1-, 2-, and 3-level pedicle subtraction osteotomy (PSO), and establish selection criteria based on preoperative radiographic parameters. Methods: Patients undergone PSO to treat ankylosing spondylitis from February 2009 to May 2019 in Sun Yat-sen Memorial Hospital of Sun Yat-sen University were enrolled. According to the quantity of osteotomy performed, the participants were divided into group A (1-level PSO, n = 24), group B (2-level PSO, n = 19), and group C (3-level PSO, n = 11). Clinical outcomes were assessed before surgery and at the final follow-up. Comparisons of the radiographic parameters and quality-of-life indicators were performed among and within these groups, and the selection criteria were established by regression. Finite element analysis was conducted to compare the biomechanical characteristics of the spine treated with different quantity of osteotomies under different working conditions. Results: Three-level PSO improved the sagittal parameters more significantly, but resulted in longer operative time and greater blood loss (p < 0.05). Greater stress was found in the proximal screws and proximal junction area of the vertebra in the model simulating 1-level PSO. Larger stress of screws and vertebra was observed at the distal end in the model simulating 3-level PSO. Conclusion Multilevel PSO works better for larger deformity correction than single-level PSO by allowing greater sagittal parameter correction and obtaining a better distribution of stress in the hardware construct, although with longer operation time and greater blood loss. Three-level osteotomy is recommended for the patients with preoperative of global kyphosis > 85.95°, T1 pelvic angle > 62.3°, sagittal vertical alignment > 299.55 mm, and pelvic tilt+ chin-brow vertical angle > 109.6°.

Objective: To compare the clinical outcomes and biomechanical characteristics of 1-, 2-, and 3-level pedicle subtraction osteotomy (PSO), and establish selection criteria based on preoperative radiographic parameters. Methods: Patients undergone PSO to treat ankylosing spondylitis from February 2009 to May 2019 in Sun Yat-sen Memorial Hospital of Sun Yat-sen University were enrolled. According to the quantity of osteotomy performed, the participants were divided into group A (1-level PSO, n = 24), group B (2-level PSO, n = 19), and group C (3-level PSO, n = 11). Clinical outcomes were assessed before surgery and at the final follow-up. Comparisons of the radiographic parameters and quality-of-life indicators were performed among and within these groups, and the selection criteria were established by regression. Finite element analysis was conducted to compare the biomechanical characteristics of the spine treated with different quantity of osteotomies under different working conditions. Results: Three-level PSO improved the sagittal parameters more significantly, but resulted in longer operative time and greater blood loss (p < 0.05). Greater stress was found in the proximal screws and proximal junction area of the vertebra in the model simulating 1-level PSO. Larger stress of screws and vertebra was observed at the distal end in the model simulating 3-level PSO. Conclusion Multilevel PSO works better for larger deformity correction than single-level PSO by allowing greater sagittal parameter correction and obtaining a better distribution of stress in the hardware construct, although with longer operation time and greater blood loss. Three-level osteotomy is recommended for the patients with preoperative of global kyphosis > 85.95°, T1 pelvic angle > 62.3°, sagittal vertical alignment > 299.55 mm, and pelvic tilt+ chin-brow vertical angle > 109.6°.

Objective: To compare the clinical outcomes and biomechanical characteristics of 1-, 2-, and 3-level pedicle subtraction osteotomy (PSO), and establish selection criteria based on preoperative radiographic parameters. Methods: Patients undergone PSO to treat ankylosing spondylitis from February 2009 to May 2019 in Sun Yat-sen Memorial Hospital of Sun Yat-sen University were enrolled. According to the quantity of osteotomy performed, the participants were divided into group A (1-level PSO, n = 24), group B (2-level PSO, n = 19), and group C (3-level PSO, n = 11). Clinical outcomes were assessed before surgery and at the final follow-up. Comparisons of the radiographic parameters and quality-of-life indicators were performed among and within these groups, and the selection criteria were established by regression. Finite element analysis was conducted to compare the biomechanical characteristics of the spine treated with different quantity of osteotomies under different working conditions. Results: Three-level PSO improved the sagittal parameters more significantly, but resulted in longer operative time and greater blood loss (p < 0.05). Greater stress was found in the proximal screws and proximal junction area of the vertebra in the model simulating 1-level PSO. Larger stress of screws and vertebra was observed at the distal end in the model simulating 3-level PSO. Conclusion Multilevel PSO works better for larger deformity correction than single-level PSO by allowing greater sagittal parameter correction and obtaining a better distribution of stress in the hardware construct, although with longer operation time and greater blood loss. Three-level osteotomy is recommended for the patients with preoperative of global kyphosis > 85.95°, T1 pelvic angle > 62.3°, sagittal vertical alignment > 299.55 mm, and pelvic tilt+ chin-brow vertical angle > 109.6°.

Objective: To compare the clinical outcomes and biomechanical characteristics of 1-, 2-, and 3-level pedicle subtraction osteotomy (PSO), and establish selection criteria based on preoperative radiographic parameters. Methods: Patients undergone PSO to treat ankylosing spondylitis from February 2009 to May 2019 in Sun Yat-sen Memorial Hospital of Sun Yat-sen University were enrolled. According to the quantity of osteotomy performed, the participants were divided into group A (1-level PSO, n = 24), group B (2-level PSO, n = 19), and group C (3-level PSO, n = 11). Clinical outcomes were assessed before surgery and at the final follow-up. Comparisons of the radiographic parameters and quality-of-life indicators were performed among and within these groups, and the selection criteria were established by regression. Finite element analysis was conducted to compare the biomechanical characteristics of the spine treated with different quantity of osteotomies under different working conditions. Results: Three-level PSO improved the sagittal parameters more significantly, but resulted in longer operative time and greater blood loss (p < 0.05). Greater stress was found in the proximal screws and proximal junction area of the vertebra in the model simulating 1-level PSO. Larger stress of screws and vertebra was observed at the distal end in the model simulating 3-level PSO. Conclusion Multilevel PSO works better for larger deformity correction than single-level PSO by allowing greater sagittal parameter correction and obtaining a better distribution of stress in the hardware construct, although with longer operation time and greater blood loss. Three-level osteotomy is recommended for the patients with preoperative of global kyphosis > 85.95°, T1 pelvic angle > 62.3°, sagittal vertical alignment > 299.55 mm, and pelvic tilt+ chin-brow vertical angle > 109.6°.

Crohn's disease (CD) is a chronic nonspecific inflammatory bowel disease that can involve the whole digestive tract. At present, the pathogenesis is believed to be mainly related to environment, genetics and intestinal microecology changes. Compared with healthy people, CD patients demonstrate different degrees of flora imbalance in the digestive tract, and the flora composition varies across different regions. In recent years, reconstruction of gastrointestinal microecological balance has become the focus of research. Fecal microbiota transplantation as a new treatment strategy has been gradually applied in clinical practice. Here we reviewed the changes of flora across different regions of digestive tract in patients with CD and the relevant pathogenic mechanism, as well as the progress of fecal microbiota transplantation in the treatment of CD.

Crohn's disease (CD) is a chronic nonspecific intestinal inflammatory disease with unclear etiology and pathogenesis. At present, it is believed that CD can cause different degrees of metabolic abnormalities, and that the related metabolites also play an important role in the development and progression of the disease. In recent years, metabonomics is becoming more and more well-developed and has provided guidance for clinicians on rational nutritional support. Here is a review on the metabolic changes of multiple systems in CD patients, the application of metabonomics in CD diagnosis and treatment, and the research progress of clinical nutrition intervention.

Objective:To establish the mice colorectal cancer (CRC) model induced by AOM/DSS with the intervention of high fat diet and probiotics, and to explore the potential mechanism of probiotics intervention in regulating intestinal flora disturbance and antitumor efficiency.Methods:Forty 8-week-old male C57BL/6J mice were randomly divided into 4 groups with 10 mice in each group: HFD group, HDF with probiotics intervention (HFD+P) group, normal diet (ND) group, normal diet with probiotics intervention (ND+P) group. The probiotic groups were administered with probiotics preparation by gavage. During the experiment, AOM/DSS was used to induce mouse colorectal cancer model. The mouse body weight was regularly recorded and the body status was evaluated weekly. High-throughput 16S rDNA sequencing was used to analyze the changes of fecal flora in bacterial structure before and after cancer induction. At the end of the experiment, intestinal tissues of mice were collected and the epididymis adipose mass (EAM) and tumor burden were recorded. The Alpha diversity index was used to analyze the abundance and diversity of the intestinal flora (higher chaol index means higher abundance of bacteria and greater Simpson index means lower diversity in flora structure). The Beta diversity index was used to analyze the significance of the difference in the distribution of intestinal flora among the four groups (When R>0, the difference in the distribution of bacteria among the groups is greater than the difference within the group).Results:After 15 weeks of experiment, the body weight of mice in HFD group, HFD+P group, ND group and ND+P group was (33.70±0.52) g, (28.70±0.32) g, (25.90±0.34) g and (25.60±0.40) g, whose difference was statistically significant ( F=700.89, P<0.01). The body weight of HFD group was higher than that of ND group and HFD+P group while the body weight of HFD+P group was still higher than that of ND group, and the differences were statistically significant (all P<0.017). The average EAM of HFD group, HFD+P group, ND group and ND+P group was (1.36±0.15) g, (0.67±0.08) g, (0.58±0.10) g and (0.54±0.05) g, whose difference was statistically significant ( F=114.03, P<0.01). Pairwise comparisons showed that EAM in HFD group was higher than that in ND group and HFD+P group respectively, with statistically significant difference (both P<0.01), while average EAM of HFD+P group was similar to ND group ( P=0.09). Under the diet intervention, the Chao1 index of HFD group, HFD+P group, ND group and ND+P group was 217.62, 235.32, 301.51 and 305.71 respectively, and the Simpson index was 0.93, 0.89, 0.91 and 0.90. At the same time, the Anosim analysis of Beta diversity analysis showed that the difference in the flora distribution among four groups was greater than the difference with in each group with statistically significant difference ( R=0.655, P=0.001). Species abundance analysis revealed that, compared with ND group, at phylum level, HFD group had a higher proportion of Bacteroides phylum and Firmicutes phylum in the intestinal flora and lower proportion of Verrucomicrobia; at genus level, the proportion of Bacteroides and Oscillibacter in HFD group was higher while the proportion of Akkermansia and Alloprevotella was lower. After the intervention of probiotics, the flora mentioned above was improved significantly except for Alloprevotella. The average number of tumor in HFD group, HFD+P group, ND group and ND+P group was 4.63±1.19, 2.33±0.52, 2.56±0.73 and 2.38±0.52 with statistically significant difference ( F=14.92, P<0.01). Conclusion:Probiotics therapy can reduce obesity and flora imbalance caused by HFD and reduce the incidence of CRC by regulating intestinal flora disturbance.

Objective:To establish the mice colorectal cancer (CRC) model induced by AOM/DSS with the intervention of high fat diet and probiotics, and to explore the potential mechanism of probiotics intervention in regulating intestinal flora disturbance and antitumor efficiency.Methods:Forty 8-week-old male C57BL/6J mice were randomly divided into 4 groups with 10 mice in each group: HFD group, HDF with probiotics intervention (HFD+P) group, normal diet (ND) group, normal diet with probiotics intervention (ND+P) group. The probiotic groups were administered with probiotics preparation by gavage. During the experiment, AOM/DSS was used to induce mouse colorectal cancer model. The mouse body weight was regularly recorded and the body status was evaluated weekly. High-throughput 16S rDNA sequencing was used to analyze the changes of fecal flora in bacterial structure before and after cancer induction. At the end of the experiment, intestinal tissues of mice were collected and the epididymis adipose mass (EAM) and tumor burden were recorded. The Alpha diversity index was used to analyze the abundance and diversity of the intestinal flora (higher chaol index means higher abundance of bacteria and greater Simpson index means lower diversity in flora structure). The Beta diversity index was used to analyze the significance of the difference in the distribution of intestinal flora among the four groups (When R>0, the difference in the distribution of bacteria among the groups is greater than the difference within the group).Results:After 15 weeks of experiment, the body weight of mice in HFD group, HFD+P group, ND group and ND+P group was (33.70±0.52) g, (28.70±0.32) g, (25.90±0.34) g and (25.60±0.40) g, whose difference was statistically significant ( F=700.89, P<0.01). The body weight of HFD group was higher than that of ND group and HFD+P group while the body weight of HFD+P group was still higher than that of ND group, and the differences were statistically significant (all P<0.017). The average EAM of HFD group, HFD+P group, ND group and ND+P group was (1.36±0.15) g, (0.67±0.08) g, (0.58±0.10) g and (0.54±0.05) g, whose difference was statistically significant ( F=114.03, P<0.01). Pairwise comparisons showed that EAM in HFD group was higher than that in ND group and HFD+P group respectively, with statistically significant difference (both P<0.01), while average EAM of HFD+P group was similar to ND group ( P=0.09). Under the diet intervention, the Chao1 index of HFD group, HFD+P group, ND group and ND+P group was 217.62, 235.32, 301.51 and 305.71 respectively, and the Simpson index was 0.93, 0.89, 0.91 and 0.90. At the same time, the Anosim analysis of Beta diversity analysis showed that the difference in the flora distribution among four groups was greater than the difference with in each group with statistically significant difference ( R=0.655, P=0.001). Species abundance analysis revealed that, compared with ND group, at phylum level, HFD group had a higher proportion of Bacteroides phylum and Firmicutes phylum in the intestinal flora and lower proportion of Verrucomicrobia; at genus level, the proportion of Bacteroides and Oscillibacter in HFD group was higher while the proportion of Akkermansia and Alloprevotella was lower. After the intervention of probiotics, the flora mentioned above was improved significantly except for Alloprevotella. The average number of tumor in HFD group, HFD+P group, ND group and ND+P group was 4.63±1.19, 2.33±0.52, 2.56±0.73 and 2.38±0.52 with statistically significant difference ( F=14.92, P<0.01). Conclusion:Probiotics therapy can reduce obesity and flora imbalance caused by HFD and reduce the incidence of CRC by regulating intestinal flora disturbance.

Objective To explore the value of methylation of SDC2 and SFRP2 genes promoter in fecal DNA for colorectal cancer ( CRC) screening. Methods All stool samples were enrolled from Changhai Hospital of Naval Medical University, the Tenth People' s Hospital of Tongji University and the Seventh Medical Center of Chinese People's Liberation Army General Hospital. A total of 500 stool samples collected from March 2018 to December 2018 were allocated to CRC group ( 132 CRCs ) , adenoma group ( 38 advanced adenomas), healthy group (152 healthy individuals), interferential group (178 cases of benign colorectal disease or other non-colorectal tumors) and negative group (330 cases composed of healthy group and interferential group ) . The promoter methylation of fecal SDC2 and SFRP2 genes was detected by methylation-specific PCR (MSP) and compared with single gene methylation and the fecal immunochemical tests ( FIT) to evaluate its sensitivity and specificity. Results The stool sample analysis showed that the sensitivity of combined detection of SDC2 and SFRP2 in CRC group was 97. 73％ ( 129/132 ) , which was significantly higher than those of the single gene SDC2 test [ 70. 45％ ( 93/132) , P=0. 000] , single SFRP2 test [81. 82％ (108/132), P=0. 000] and FIT [69. 70％ (92/132), P=0. 000]. In adenoma group, the sensitivity of combined detection of SDC2 and SFRP2 was 57. 89％ (22/38), which was significantly higher than those of the single gene SDC2 test [ 15. 79％ ( 6/38 ) , P= 0. 000 ] and FIT [ 21. 05％ ( 8/38 ) , P=0. 021] , with no significant difference compared with that of SFRP2 test [ 47. 37％ ( 18/38) , P=0. 358] . In healthy group, the specificity of combined detection of SDC2 and SFRP2 was 98. 68％ (150/152), with no significant difference compared with those of single gene SDC2 test [ 100. 00％( 152/152) , P=0. 156] , single SFRP2 test [98. 68％ (150/152), P=1. 000] or FIT [95. 39％ (145/152), P=0. 091]. Specificities of combined detection of two genes in interferential and negative groups were 90. 45％ ( 161/178) and 94. 24％( 311/330) , which were significantly higher than 73. 03％( 130/178, P=0. 000) and 83. 33％( 275/330, P=0. 000) of FIT, respectively. Conclusion The combined detection test of methylation of SDC2 and SFRP2 is superior to single gene test, whose sensitivity of CRC and aggressive adenoma and specificity of distinguishing benign and malignant lesions are higher than FIT, which has potential application value.