Objective To systematically evaluate the differences in clinicopathologic features and prog-nosis of colorectal cancer(CRC)between youth and middle-aged and elderly people.Methods The relevant literatures in Chinese and English databases before June 2024 were retrieved.The Stata 18 and RevMan5.3 softwares were used to perform the heterogeneity and sensitivity analyses as well as publication bias tests for the relevant outcome indicators.Results A total of 17 case-control studies were included,including a total of 6 817 patients with pathologically diagnosed CRC,among them 1 939 cases in the young group and 4 878 cases in the middle-aged and elderly group.The results of meta analysis showed that the proportion of family histo-ry in the young adult group(OR=3.09,95%CI:2.33-4.09),misdiagnosis rate(OR=4.40,95%CI:3.30-5.86),proportion of poorly differentiated carcinomas(OR=3.57,95%CI:2.73-4.67),proportion of mucin-ous adenocarcinomas and imprinted cell carcinomas(OR=3.41,95%CI:2.79-4.18),and proportion of TNM stage at diagnosis(stage Ⅲ-Ⅳ,OR=1.71,95%CI:1.44-2.02),incidence rate of lymph node metas-tasis(OR=1.92,95%CI:1.61-2.28),incidence rate of distant metastasis(OR=2.09,95%CI:1.53-2.86)were higher than those in the middle-aged and elderly group(all P<0.05);the CEA-positive rate at diagnosis(OR=0.68,95%CI:0.57-0.80)and 5-year survival rate(OR=0.24,95%CI:0.16-0.36)in the young group were lower than those in the middle-aged and elderly group(all P<0.05).The difference in the tumor diameter size(OR=1.32,95%CI:0.98-1.77)between the two groups was not statistically significant(P=0.07).Conclusion Compared with middle-aged and elderly CRC,young patients with CRC has a closer famil-ial correlation,may be more easily misdiagnosed clinically,its malignant degree would be higher,and the TNM stage in diagnosis is relatively late;in clinic the young population with CRC high risk could be appropriately relaxed in the age limit for screening.

Objective To design a custom 3D printed monoblock acetabular implant for reconstructing PaproskyⅢA acetabular bone defects and to analyze the stress distribution,displacement,and clinical reliability of the implant and surrounding bone using finite element analysis(FEA).Methods Bilateral hip computed tomography(CT)data of a patient with PaproskyⅢA acetabular bone defects were collected.Models were developed and analyzed using Mimics Medical 21.0,Geomagic Wrap 2021,Solidworks 2023,and ANSYS Workbench 2022 R1 softwares.The biomechanical performance of the custom 3D printed monoblock acetabular implant was simulated under a single-leg stance condition.Results The peak von Mises stress of the hip components was observed at the femoral stem,measuring 67.318 MPa.For the custom 3D printeded monoblock acetabular implant,the peak stress was located at the anterosuperior contact area between the implant and acetabular bone,measuring 6.935 MPa.The femoral stem exhibited a peak stress of 67.318 MPa at its junction with the femoral head.The liner's peak stress was 1.333 MPa near the fixation of screw 9 at the superior part of the acetabular cup.The screws showed a peak stress of 2.215 MPa at the junction with the implant.For the cortical bone,the peak stress was 9.844 MPa at the distal femur,while the cancellous bone exhibited a peak stress of 0.701 MPa at its distal connection with the femoral stem.The pelvic bone's peak stress was 8.002 MPa at the anterior transition zone between the normal acetabulum and the defect.The peak micromotion of the custom 3D printed monoblock acetabular implant at its posterosuperior area,measuring 0.114 mm.The femoral stem and head exhibited a peak micromotion of 0.132 mm at the contact interface with the acetabular liner.The micromotion range at the implant-acetabular bone interface was 0.098 mm to 0.131 mm.Conclusion Under a simulated single-leg stance condition,the stress distribution in all components and the acetabular bone surface remains below their respective yield strengths.The micromotion threshold between the acetabular cup and acetabular bone is within acceptable limits.Biomechanical analysis indicates that the patient can perform early weight-bearing rehabilitation postoperatively.However,walking or jogging rehabilitation should be approached with caution.

BACKGROUND:Bone mineral density is the clinical gold standard for determining bone strength,but bone mineral density is less sensitive to changes in bone mass,with large changes in bone mineral density only occurring when bone mass is significantly reduced,so bone mineral density has limited ability to predict changes in bone strength and fracture risk. OBJECTIVE:A model of the normal and osteoporotic hip joint was developed to analyze the stresses and deformation in the hip of normal and osteoporotic patients under single-leg standing conditions. METHODS:A healthy adult female volunteer at the age of 36 years was selected as the study subject.The CT data of the hip joint of this volunteer were obtained and saved in DICOM format.The hip joint model was reconstructed in three dimensions,and the material properties were assigned by the gray value assignment method to obtain the normal and osteoporotic hip joint models according to the empirical formula.The same boundary conditions and loads were set to simulate the stresses and deformation in the normal and osteoporotic hip joints in the single-leg standing position. RESULTS AND CONCLUSION:(1)In the finite element model of the normal and osteoporotic hip,the stress distribution was more concentrated in the medial region of the femoral neck.(2)In the hip bone,the stress distribution was mainly concentrated in the upper part of the acetabulum.(3)The stress peaks in the medial femoral neck and upper acetabulum were larger in the normal hip model than in the osteoporotic hip model,probably due to the reduced bone strength of the osteoporotic bone.(4)The peak Von Mises of both normal and osteoporotic hip models were concentrated on the medial femoral neck,and the peak Von Mises of the hip bone was smaller,indicating that the overall effect of osteoporosis on hip bone stresses was relatively small.(5)In terms of deformation in the single-leg standing position,the maximum deformation in the normal hip model was located at the acetabulum and femoral head,and the maximum deformation was located at the upper part of the greater trochanter of the femur.(6)It is suggested that the finite element analysis method to model the values of parameters related to bone tissue in osteoporosis may improve clinical prediction of bone strength changes and fracture risk.It is explained from the biomechanical view that the intertrochanteric femur and femoral neck are good sites for osteoporotic hip fractures.

Objective To address the radioactive contamination of wounds caused by transuranic nuclides, wound radiation imaging based on coded aperture imaging technology was investigated. Methods By simulating multiple source terms using Monte Carlo method, the differences in imaging performance between two image reconstruction algorithms under near-field conditions were compared. The effects of detector pixels and detection plane pixels on image resolution were investigated. Results The imaging system was simulated based on the designed dimensions. The simulated imaging field of view was 89.4 mm × 89.4 mm and the simulated angular resolution was 1.98°. Based on the comparison of the average width at half height of the reconstructed point sources under different conditions, it was found that increasing the number of pixels in the detector and detection plane optimized the angular resolution but significantly prolonged the Monte Carlo simulation time. Conclusion According to the simulation results, the parameters of the imaging system can be used to effectively image radioactive contamination. Our results provide methodological support for the measurement of wound contamination caused by transuranic nuclides, and lay the foundation for the development of wound contamination imaging detection systems in the future.

OBJECTIVE To investigate the transfer and diffusion of berberine hydrochloride(BBH), the main active component of Coptis and Phellodenticum in the system of carboxymethyl chitosan(CMCS)-sodium alginate(SA). METHODS CMCS and SA were stirred in a certain proportion, and D-gluconolactone(GDL) was added to form polyelectrolyte hydrogel. Rheometer was used to study the rheological properties of CMCS-SA hydrogel, including the elastic modulus G′ and the viscous modulus G′′. A BBH diffusion model for CMCS-SA hydrogel was designed, and the relevant rules of BBH permeation through CMCS-SA polyelectrolyte hydrogel were observed by UV-VIS. RESULTS The elastic modulus G′ of the hydrogel was measured when the ratio of CMCS to SA was 3∶1, 2∶1, 1∶1, 1∶2, and 1∶3. When the ratio of CMCS to SA was 1∶1, G′ was the highest, and the crosslinking strength of the hydrogel was the highest. The cumulative amount of BBH transfer was measured by the BBH transfer model, and the diffusion of BBH in CMCS-SA hydrogel was fitted as the skeleton dissolution by Peppas equation, indicating that BBH dissociation and the transfer efficiency increased as the amino group of CMCS decreased or the carboxyl group of SA increased. The elastic modulus G′ of CMCS-SA hydrogel increased with the increase of GDL content. The reason was that the binding force between CMCS and SA molecules gradually increased with the decrease of pH, and the crosslinking degree of the hydrogel was enhanced. When ratio of fixed CMCS to SA was 1∶1 and the GDL content was 0.15 g·mL−1, the formability of CMCS-SA hydrogel was good. In addition, when BBH was transferred in hydrogel with different concentrations of GDL, the transfer efficiency increased with the increase of GDL content. When BBH was delivered in different thickness hydrogel, the delivery efficiency of CMCS-SA hydrogel increased with the decrease of thickness. CONCLUSION The CMCS-SA hydrogel system, as a potential drug carrier for traditional Chinese medicine extracts such as BBH, is expected to serve as a gel carrier for transdermal drug delivery.

Alzheimer's disease(AD)is one of the most common types of dementia in clinical practice.The increased permeability of the gut and blood-brain barrier caused by intestinal microecological dysbiosis may be an important incentive to affect the incidence of AD.Gut microbiota regulates the central nervous system through the gut microbiota-gut-brain axis(gut-brain axis),and plays an important role in the cognitive func-tion,occurrence and development of clinical symptoms in AD patients.This review comprehensively reviewed the current literature on the relationship between gut microbiota dysregulation and inflammatory cytokine changes in AD,and the treatment of AD targeting with gut microbiota,so as to clarify the new progress in the influence of intestinal microecology changes on the cognitive function of AD patients,the potential diagnosis in the early onset of AD,and the potential mechanism of gut microbiota participating in the regulation of AD.It provides a new idea for the treatment strategy of AD.

Objective:To investigate the clinical features of neonatal testicular torsion and to evaluate the effect and necessity of early intervention.Methods:A retrospective analysis was performed on 11 neonates admitted to the Second Hospital of Shandong University with neonatal testicular torsion from June 2017 to June 2022. Clinical data of these cases including clinical manifestations, ultrasonography findings, surgical management and outcomes were reviewed and analyzed with descriptive statistical methods.Results:The median age of the 11 patients on admission was 2.6 d (1-5 d). The median time from finding abnormal scrotum to admission was 12 h (1-120 h). Various degrees of scrotal swelling or scleroma were found in the patients. Among them, seven patients presented with acute inflammatory signs of cyano sis or skin redness, and testis-like tissue induration could be touched. Ultrasound scan showed abnormal blood flow in the affected testicle in all cases. Emergency scrotal exploration under general anesthesia was performed successfully in all cases and ten of them underwent orchiectomy of the affected testicle plus contralateral orchiopexy. The rest one who was admitted within 1 h after birth only underwent orchiopexy of the affected testicle as the parents refused contralateral testicular exploration. During the operation, 12 twisted testis were observed, including seven with extravaginal torsion, three with intravaginal torsion and two adhering to the surrounding tissue without normal testicular tissue or distinguishable torsion direction or degree. In this study, ten patients had unilateral testicular torsion, which affected the left side in seven cases and the right side in three cases, and one had bilateral testicular torsion, which was diagnosed as left testicle torsion before surgery. During scrotal exploration, the left testicle of this bilateral case was resected due to necrosis, while the right testicle twisted about 180 degrees with good blood flow and was subjected to orchidopexy after reduction. In one case, the unaffected testicle was unfixed and dysplastic during contralateral exploration, which was also subjected to orchidopexy. In the 12 testis with torsion, one testicle of the patient admitted within 1 h after birth and the right testicle of the bilateral case were preserved with a salvage rate of 2/12. Pathological examination showed necrosis in the ten excised testis, and fibrosis and calcification foci in two of them. None of the patients had any perioperative complications and the scrotal incision healed well in all neonates. The patients were followed up for 6-12 months with regular ultrasound. The two preserved testis and the contralateral testis subjected to orchidopexy were located in the scrotum with good blood supply, and no torsion, atrophy or other abnormalities occurred.Conclusions:Neonatal testicular torsion is rarely seen in clinical practice and has no specific manifestations. It has a high excision rate due to testicular necrosis. Early diagnosis and bilateral scrotal exploration are crucial to the prognosis and the keys to save the affected testis and avoid anorchidism.

Objective:To investigate the effect of 3D-printed customized flanged cup in hip revision with severe acetabular bone defects.Methods:Since February 2017, 10 cases of 3D-printed customized flanged cups were used in hip revision with severe acetabular bone defects, including 2 cases of Paprosky type IIIA and 8 cases of Paprosky type IIIB. There were 5 males and 5 females, mean age 73.6±8.1 yrs (range, 62-87 yrs), 5 left and 5 right cases. The preoperative thin-layer CT scan was preformed to reverse reconstruct digital pelvis. Five cases of one-piece flanged cups and 5 cases of decomposed flanged cups, including 3 cases of composite one-piece cups were designed by computer. The surgery was performed strictly according to the plan.Postoperative follow-up was performed to evaluate the Harris score. Operation time,intraoperative bleeding and other complications such as vascular and nerve injury, postoperative infection, and dislocation were counted. Pelvic X-ray was used to assess the height and horizontal position of the center of rotation and the stability of the prosthesis.Results:The surgical procedure was successful, with an average operative time of 147.9±48.3 min (range, 96-212 min) and an average intraoperative bleeding of 730.4±262.6 ml (range, 500-1 300 ml). The mean time of final follow-up was 40.8±18.7 months (range, 16-70 months) after surgery. At the last follow-up, the average Harris score was 83.80±6.73, with 4 cases excellent, 5 cases good, and 1 case fair. The excellent and good rate was 90%. The last Harris score was significantly higher than that before operation 28.60±8.40 ( t=16.84, P<0.001). The height of affected hip joint rotation center decreased from 46.24±7.74 mm before operation to 15.54±2.54 mm after operation with significant difference ( t=14.61, P<0.001). It was slightly higher than the opposite side (13.81±1.48 mm), which had no significant difference ( t=1.83, P=0.100). The horizontal distance of affected hip joint rotation center increased from 33.79±5.27 mm before operation to 40.53±4.50 mm after operation with significant difference ( t=3.62, P=0.006). It had no significant difference ( t=1.28, P=0.232) compared with the opposite side (38.54±3.46 mm). All incisions were healed in one stage without infection, vascular or nerve injury. During the following-up, all prostheses were in satisfied position without loosening, dislocation or screw breaks. Conclusion:Digitally assisted 3D-printed flanged cups can be used in hip revision with severe acetabular bone defect. It can not only improve hip joint function, but also restore the acetabular rotation center and the prosthesis stability, which can achieve good early and mid-term effect.

Objective:To analyze the efficacy of the reconstruction of the proximal humerus by reverse shoulder arthroplasty with three-dimensional (3D) printing technology after tumor rescetion.Methods:A retrospective analysis was conducted on the data of eight patients undergoing semi-constrained reverse shoulder arthroplasty with 3D printing technology after the resection of bone tumors in proximal humeri at the Affiliated Wuxi People's Hospital of Nanjing Medical University from December 2017 to January 2021. There were four males and four females with an average age of 55.1 (range, 31-73) years, all of whom had unilateral onset, 2 on the left and 6 on the right. There was one case of leiomyosarcoma (Enneking IIB), two cases of chondrosarcomas (one Enneking IA and one Enneking IB), four cases of Campanacci grade 3 giant cell tumor of bone, and one case of bone metastasis of lung adenocarcinoma. Individualized prosthesis and implantation protocol were completed preoperatively in all patients. The glenoid baseplate was manufactured using 3D printing technology. During the surgery, Malawer type I tumor resection and semi-constrained reverse shoulder arthroplasty were performed, with 6 cases simultaneously using allograft-prosthetic composite reconstruction. The follow-up was scheduled, and the patient received X-ray examination of the shoulder. The range of motion of the shoulder was measured, the Constant-Murley score and musculoskeletal tumor society (MSTS) score were recorded.Results:All 8 patients successfully completed the surgery, with a surgical time of 173.8±46.7 min (range, 130-260 min), intraoperative blood loss of 487.5±334.6 ml (range 200-1,200 ml), and proximal humeral resection of 9.9±4.6 cm (range, 4.5-19.0 cm). All patients were followed up for a period of 45.6±12.5 months (range, 24-60 months). At the last follow-up, the abduction ranges of motion of the affected shoulders increased from 27.5°±14.4° pre-operatively to 106.3°±21.8° post-operatively, with a statistically significant difference ( t=11.37, P<0.001). The forward flexion ranges increased from 28.1°±12.8° pre-operatively to 115.6°±24.0° post-operatively, with a statistically significant difference ( t=11.49, P<0.001). The Constant-Murley score was improved from 40.5±14.3 pre-operatively to 79.3±11.2 post-operatively, with a statistically significant difference ( t=9.58, P<0.001). The MSTS score was 25.6±2.2 (range, 23-28), including 6 excellent cases and 2 good cases. At 2 weeks after surgery, one patient experienced joint dislocation that was successfully reduced manually. Up to the final follow-up, all patients had survived without local tumor recurrence, metastasis, prosthesis infection and loosening. Conclusion:3D printing technology assisted shoulder arthroplasty is helpful for effective reconstruction and shoulder joint function recovery after resection of proximal humeral tumors, with satisfactory outcomes in the early and middle stages.

It is a common problem for all mentors to cultivate the capacity for scientific research of master degree candidates in plastic surgery under the current training program of "double-track in one" and "four-certificate in one". This study introduces the "COME" training mode that includes clinical study, off-hour, multiple modalities, and efficient feedback. This study elaborates the composition and method of this training mode, and compares the number and quality of published papers and thesis before and after its implementation. Results show that the "COME" training mode can significantly improve the capacity for scientific research of master degree candidates in plastic surgery.