BACKGROUND: Most reported biomechanical studies on sacroiliac joint injury and fixation use cadavers or artificial bone models to simulate the sacroiliac joint injury.OBJECTIVE: To analyze the vertical stability of anterior plate fixation for sacroiliac joint dislocation using three-dimensional finite element method. METHODS: The anterior plate fixation model of unilateral sacroiliac joint dislocation was constructed on the basis of the three-dimensional finite element model of a complete pelvis. An axial load of 500 N was applied on the model; the cloud pictures of stress, strain and displacement were obtained after calculation and compared with that of the complete pelvis under the same conditions.RESULTS AND CONCLUSION: Stress concentration occurred at the internal fixation system; the maximum stress was found at the screws near the injured sacroiliac joint, far greater than the maximum stress of the complete pelvis under the same condition. The maximum strain was found in the healthy sacroiliac joint; the fixed sacroiliac joint had no strain. The maximum displacement was found in the injured sacroiliac joint; it was about twice longer than the complete pelvis. These findings indicate that the vertical stability of pelvis is poor using anterior plate internal fixation treatment for sacroiliac joint dislocation; and stress concentration occurs at the screws and plates.

BACKGROUND: Lateral collateral ligaments play an important role in maintaining knee stability.Motion reduction of knee joint can be realized and the changes laws of medial and lateral collateral ligaments' length after anterior cruciate ligament(ACL)injury during weight-bearing flexion can be obtained via 2D/3D image registration technique.OBJECTIVE: To study in vivo stability of length changes of the medial and lateral collateral ligaments of ACL injury knee during weight-bearing flexion.METHODS: Eight volunteers with unilateral ACL rupture and contralateral normal knees,was captured CT images and 2orthogonal images of the knee at 0,15°,30°,60°,and 90° of weight-bearing flexion.These orthogonal images were used to recreate the in vivo knee positions at each of the targeted flexion angles by the method of 2D/3D image registration.Through the bone insertion of medial and lateral collateral ligaments,the elongation changes of medial and lateral collateral ligaments were obtained.RESULTS AND CONCLUSION: At 0°,15° and 30°,the length of medial collateral ligament of ACL injury knees was longer than normal knees,but the lateral collateral ligaments length of ACL injury knee was shorter than that of normal knees.All the differences have statistical significances(P < 0.05).The findings demonstrated that,at 0°,15° and 30°,the medial collateral ligament length of ACL injury knees was longer than normal knees,but lateral collateral ligaments length of ACL injury knees was shorter than normal knees.

Objective To compare a novel mirror-overlap method with the traditional manual measurement and the subjective assessment in assessing breast symmetry after oncoplastic surgery.Methods 59 patients with breast cancer who underwent conservation/reconstruction surgery were recruited.The post-operative assessment for breast symmetry was conducted using manual measurement,subjective assessment by the patient,their family member and a nurse,and the mirror-overlap method respectively.The latter method involved using the Photoshop to assess the area differences in breast outlines and shadows created by a flashlight when bilateral images were overlapped in the axis of midline.Results The distance differences between bilateral breasts measured using manual method were negatively correlated with symmetric coefficients in the mirror-overlap method (P＜0.05).There was a positive correlation between the average scores in the subjective assessment and symmetric coefficients of mirror-overlap method (P＜0.05).Conclusion The mirror-overlap method is an easy,feasible and cheap method which collects 3D breast information and provides an effective approach to assess breast symmetry after oncoplastic surgery.

Gastric stem cells are adult stem cells found in the gastric tissues,which possess high self-renewal capability,proliferation rate and multiple differentiation capability.They can regenerate all the gastric mucosa epithelial cells.Gastric stem cells play an important role in the self-renewal and injury repair,making epithelium of gastric mucosa in the dynamic balance and maintaining the integrity of gastric mucosa.With the constant deepening of stem cell research,the application of gastric stem cells provides a new means for the study of gastric physiology and diseases.Since the first report by Barker in 2010,gastric organoids have soon become a model of interest and are highly desirable as tools for studying gastric diseases.As an optimal experimental model,gastric organoids are superior to animal model and conventional cell culture.Gastric organoids are comprised of all major types of gastric epithelial cells,represent the architecture and function remarkably similar to those of the gastric epithelium,faithfully recapitulating the functional gastric epithelium ex vivo.Especially gastric organoids derived from the human body,which allow the investigation of the function of human stomach in the ex vivo setting.In this review,research progresses of gastric stem cells and their application in establishment of gastric organoids are summarized.

Gastric organoid is the organotypic cultures of gastric stem cells or pluripotent stem cells. Gastric organoid is comprised of all major types of gastric epithelial cells and represent the architecture and function remarkably similar to those of the gastric epithelium, faithfully recapitulating the functional gastric epithelium ex vivo. As ideal basic experimental model, gastric organoid has advantages over animal models and conventional cell model in many aspects. Gastric organoid derived from human gastric tissue, in particular, allows the investigation of the function of human stomach in the ex vivo setting. It has now been applied in the field of formation and physiology of the stomach, Helicobacter pylori infection-associated diseases, research of the pathogenic gene, screening and development of drugs, and regenerative medicine. What is more, as an innovative pre-clinical cancer model, gastric cancer organoid has provided important insights in the development of gastric cancer and screening of antitumor drugs, such as simulating the occurrence and development of gastric cancer, screening and development of antitumor drugs, personalized medication and targeted therapy for gastric cancer, and combined application with patient-derived xenograft. In this review, we summarize the establishment and application of gastric and gastric cancer organoids, especially in modeling gastric cancer, basic research and drug development.
Helicobacter Infections ; Humans ; Organ Culture Techniques ; standards ; trends ; Organoids ; Research ; trends ; Stomach Neoplasms

Colonic organoids are three-dimensional organotypic cultures of the colonic stem cells or pluripotent stem cells. Its essence is the culture of colonic stem cells or pluripotent stem cells, and their derived intestinal epithelial cells, intestinal endocrine cells and goblet cells in basement membrane extract with specific growth factors. Colonic organoids are comprised of all major types of colonic epithelial cells and represent the architecture and function remarkably similar to those of the colonic epithelium, faithfully recapitulating the functional colonic epithelium ex vivo. As a superior basic experimental model, colonic organoids are representing advantages over conventional cell models and animal models in many aspects, such as high successful rate, short productive cycle, and high consistency with source tissue. Since first reported in 2011, colonic organoids have soon become an important topic in the field of colonic diseases. It has now been applied in the field of physiology of colonic epithelium, infectious diarrhea, ulcerative colitis, regeneration of intestinal injury, and colon tumors. In this review, we summarize the research advances of establishment and application of colonic organoids.