OBJECTIVE: To evaluate the effect of biodegradable magnesium alloy materials in promoting tendon-bone healing during rotator cuff tear repair and to investigate their potential underlying biological mechanisms. METHODS: Forty-eight 8-week-old Sprague Dawley rats were taken and randomly divided into groups A, B, and C. Rotator cuff tear models were created and repaired using magnesium alloy sutures in group A and Vicryl Plus 4-0 absorbable sutures in group B, while only subcutaneous incisions and sutures were performed in group C. Organ samples of groups A and B were taken for HE staining at 1 and 2 weeks after operation to evaluate the safety of magnesium alloy, and specimens from the supraspinatus tendon and proximal humerus were harvested at 2, 4, 8, and 12 weeks after operation. The specimens were observed macroscopically at 4 and 12 weeks after operation. Biomechanical tests were performed at 4, 8, and 12 weeks to test the ultimate load and stiffness of the healing sites in groups A and B. At 2, 4, and 12 weeks, the specimens were subjected to the following tests: Micro-CT to evaluate the formation of bone tunnels in groups A and B, HE staining and Masson staining to observe the regeneration of fibrocartilage at the tendon-bone interface after decalcification and sectioning, and Goldner trichrome staining to evaluate the calcification. Immunohistochemical staining was performed to detect the expressions of angiogenic factors, including vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2), as well as osteogenic factors at the tendon-bone interface. Additionally, immunofluorescence staining was used to examine the expressions of Arginase 1 and Integrin beta-2 to assess M1 and M2 macrophage polarization at the tendon-bone interface. The role of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway in tendon-bone healing was further analyzed using real-time fluorescence quantitative PCR. RESULTS: Analysis of visceral sections revealed that magnesium ions released during the degradation of magnesium alloys did not cause significant toxic effects on organs such as the heart, liver, spleen, lungs, and kidneys, indicating good biosafety. Histological analysis further demonstrated that fibrocartilage regeneration at the tendon-bone interface in group A occurred earlier, and the amount of fibrocartilage was significantly greater compared to group B, suggesting a positive effect of magnesium alloy material on tendon-bone interface repair. Additionally, Micro-CT analysis results revealed that bone tunnel formation occurred more rapidly in group A compared to group B, further supporting the beneficial effect of magnesium alloy on bone healing. Biomechanical testing showed that the ultimate load in group A was consistently higher than in group B, and the stiffness of group A was also greater than that of group B at 4 weeks, indicating stronger tissue-carrying capacity following tendon-bone interface repair and highlighting the potential of magnesium alloy in enhancing tendon-bone healing. Immunohistochemical staining results indicated that the expressions of VEGF and BMP-2 were significantly upregulated during the early stages of healing, suggesting that magnesium alloy effectively promoted angiogenesis and bone formation, thereby accelerating the tendon-bone healing process. Immunofluorescence staining further revealed that magnesium ions exerted significant anti-inflammatory effects by regulating macrophage polarization, promoting their shift toward the M2 phenotype. Real-time fluorescence quantitative PCR results demonstrated that magnesium ions could facilitate tendon-bone healing by modulating the PI3K/AKT signaling pathway. CONCLUSION Biodegradable magnesium alloy material accelerated fibrocartilage regeneration and calcification at the tendon-bone interface in rat rotator cuff tear repair by regulating the PI3K/AKT signaling pathway, thereby significantly enhancing tendon-bone healing.
Animals ; Rotator Cuff Injuries/metabolism* ; Rats, Sprague-Dawley ; Signal Transduction ; Wound Healing/drug effects* ; Alloys/pharmacology* ; Rats ; Proto-Oncogene Proteins c-akt/metabolism* ; Rotator Cuff/metabolism* ; Macrophages/metabolism* ; Magnesium/pharmacology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Vascular Endothelial Growth Factor A/metabolism* ; Male ; Biocompatible Materials ; Bone Morphogenetic Protein 2/metabolism*

Objective To compare the efficacy of 2 L and 3 L polyethylene glycol(PEG)electrolyte solution for bowel preparation in a real-world setting.Methods A real-world,single-center cohort study was conducted on the individuals undergoing colonoscopy in Department of Gastroenterology of Chengdu Third People's Hospital between May and October 2023.Based on our inclusion and exclusion criteria,they were given 2 L(n=4 684)and 3 L(n=3 700)PEG electrolyte solution for bowel preparation.The primary outcome indicator was the adequacy of bowel preparation by Boston bowel preparation score(BBPS).Secondary outcome indicators included the BBPS score,polyp detection rate(PDR),tolerability,compliance,and incidence of adverse events.Results The adequacy rate of bowel preparation was 94.35％in the 3 L group,significantly higher than that of the 2 L group(91.29％,P＜0.001).The 3 L group obtained a higher BBPS score then the 2 L group(6.92±1.06 vs 6.81±1.14,P＜0.001).But there was no statistical difference in the PDR between the 2 groups(P=0.073).And the rate of PEG completion(P=0.810),administration of low residue diet as required(P=0.094)or use of dimethicone(P=0.072)were comparable between the 2 groups.However,the incidences of vomiting(4.5％vs 3.2％,P=0.002),abdominal discomfort(5.0％vs 3.9％,P=0.011)and sleep disturbance(18.0％vs 14.6％,P＜0.001)were obviously higher in the 3 L group than the 2 L group.Conclusion In a real-world setting,2 L PEG is a considerably safe and effective regimen for bowel preparation.

Objective To evaluate the treatment of current status and prognosis in childhood APL with APL2008 ,which was administrated since 2008 in our center .Methods A total of 43 children with newly diagnosed APL between 2008 to 2014 were studied retrospectively .Treatment options and current status were summarized from 28 patients who received APL2008 therapy . Results Studied 43 patients were at median age of 8 years and 4 months ,with 28 boys and 15 girls .The main clinical manifestations were infection ,anemia ,bleeding ,fever ,hepatomegaly ,splenomegaly and lymphadenopathy .The proportions of low ,intermediate and high risk groups were 27 .9% ,48 .8% and 23 .3% ,respectively .Eleven cases could be diagnosed as DIC .Bone marrow morphology showed abnormal elevation of promyelocyte .37 patients had distinctive immunophenotype such as frequent expression of CD33 , CD117 and MPO .PML/RARαfusion gene positive rate was 100% in 43 children and cytogenetic analysis were positive in 37 cases , of which specific genetic lesion in APL cells with t (15 ;17)(q22 ;q12) was found in 28 cases ,and karyotypes was found in 9 cases as infrequent chromosomal abnormalities .In 43 patients ,4 cases were early dead from intracranial hemorrhage at early stage ,and 11 cases were given up early .There were only 2 cases dead ,2 cases relapsed and 1 case lost among 28 APL children ,which enabled ef‐ficacy analysis possible .96 .4% of these 28 cases achieved HCR .The 2 year Kaplan Meier estimates of OS and EFS were 85 .9% ± 7 .6% and 80 .4% ± 8 .8% .But OS and EFS would be 94 .7% ± 5 .1% and 88 .9% ± 7 .4% if 3 patients who had non standard treat‐ment were excluded .Conclusion Childhood APL were characterized by anemia ,bleeding ,fever and infiltration .APL′s coincidence rate between PML/RARa fusion gene and morphology ,immunology and cytogenetics were 95 .3% ,90 .2% and 86 .5% ,respective‐ly .APL2008 significantly improved the prognosis of APL .