Reconstruction for extensive sacrococcygeal defects in complex tumor patients with personalized customized gluteus maximus myocutaneous flaps.

AIM: To evaluate the clinical effects of personalized customized gluteus maximus myocutaneous flaps (GMMF) for reconstruction of extensive sacrococcygeal soft tissue defects in complex tumor patients. METHODS: A retrospective chart review was conducted on 8 patients who underwent personalized customized GMMF reconstruction for large sacrococcygeal defect from December 2021 to August 2023. The personalized customized GMMF were designed based on the variations of tissue defect in location, shape and volume of different dead spaces. The principle of the personalized GMMF is to ensure that the rotation point of the flap can reach the farthest end of the defect. Patient demographics, operative characteristics, and perioperative risk factors were analyzed. Clinical outcomes were assessed, focusing on complications such as flap necrosis, wound dehiscence, infection, seroma, and hematoma. RESULTS: Six patients with rectal cancer and two with sacral tumors underwent personalized customized GMMF reconstruction for extensive sacrococcygeal defects. The average volume of the wound cavity was 104 mL, with a mean vertical depth was 10.8 cm. Six patients had low serum albumin (<35 g/L). After a mean follow-up of 15.5 months, no major complications occurred, except for one seroma that resolved within 2 weeks. CONCLUSION: The personalized customized GMMF described in this study is an effective method for reconstructing large sacrococcygeal wounds with significant depth in complex tumor patients. It allows for greater rotation of the muscle flap into the sacrococcygeal wound defect and provides adequate blood supply by utilizing the bulk of muscle tissue to obliterate dead space.

Management of a complicated colonexposed sacrococcygeal wound after pelvic exenteration: a case report.

DECLARATION OF INTEREST: This work was supported by the Naval Medical University and the University of Shanghai for Science and Technology Joint Projects (2020-RZ04), the Innovative Clinical Research Program of Shanghai Changzheng Hospital (2020YLCYJ-Y16), and the academic project of Naval Medical University (2022QN073). The authors have no conflicts of interest to declare.

A novel p.Pro871Leu missense mutation in SPECC1L gene causing craniosynostosis in a patient.

INTRODUCTION: Craniosynostosis is one of the most common craniofacial abnormalities. It involves premature closure of one or more cranial sutures. Mutations in many genes have been and continue to be identified in patients. SETTINGS AND SAMPLE POPULATION: Whole blood samples were collected from the patient and family members. MATERIAL AND METHODS: Whole exome sequencing was performed to identify potential mutations in the patient. The results were verified by Sanger sequencing by comparing SPECC1L gene sequence of blood samples from 100 unrelated population-matched controls. RESULTS: The patient presented with craniosynostosis with fusion of the bicoronal and sagittal sutures. A novel missense mutation (c.2612C>T, p.Pro871Leu) in the SPECC1L gene was identified. Gene analysis showed a missense mutation in exon1 of SPECC1L that led to an amino acid substitution in the region between coiled-coil domain 3 and calponin homology domain. CONCLUSION: Our observations expand the molecular spectrum of gene mutations in craniosynostosis and emphasize the importance of gene testing in the diagnosis of craniosynostosis. The observations also reinforce the characteristics of SPECC1L-related cranial disorders.

BMP-2 and VEGF-A modRNAs in collagen scaffold synergistically drive bone repair through osteogenic and angiogenic pathways.

Bone has a remarkable potential for self-healing and repair, yet several injury types are non-healing even after surgical or non-surgical treatment. Regenerative therapies that induce bone repair or improve the rate of recovery are being intensely investigated. Here, we probed the potential of bone marrow stem cells (BMSCs) engineered with chemically modified mRNAs (modRNA) encoding the hBMP-2 and VEGF-A gene to therapeutically heal bone. Induction of osteogenesis from modRNA-treated BMSCs was confirmed by expression profiles of osteogenic related markers and the presence of mineralization deposits. To test for therapeutic efficacy, a collagen scaffold inoculated with modRNA-treated BMSCs was explored in an in vivo skull defect model. We show that hBMP-2 and VEGF-A modRNAs synergistically drive osteogenic and angiogenic programs resulting in superior healing properties. This study exploits chemically modified mRNAs, together with biomaterials, as a potential approach for the clinical treatment of bone injury and defects.

Effects of physiological aging factor on bone tissue engineering repair based on fetal BMSCs.

BACKGROUND: At present, many laboratories and hospitals all over the world are attempting and exploring the clinical transformation of this tissue engineered bone graft (TEBG) strategy. Many successful cases of bone tissue engineering (BTE) repair were based on young individuals. But there are little studies about the effectiveness of TEBG strategy in physiological aged individuals. METHODS: In this research, we studied whether aging factor has influence on the skull repair effect of Fetal-TEBG, at the level of the large animal models. We used the fetal bone marrow stromal cells (Fetal-BMSCs) as the seed cells, combining the decalcified bone matrix (DBM) scaffolds, to repair the skull defects of the aged goats and the young goats. The repair effects on both aged goat and young goat were compared by Micro-CT and histology examination. RESULTS: The skull defects of the young goats could be repaired better than that of the aged goats after 6 months by Fetal-TEBG; In the aged goats, although not completely repaired, the defects repaired by Fetal-TEBG was better than that repaired by the Control DBM scaffold. CONCLUSIONS: Aging factor has impact on the bone repair effect of Fetal-TEBG; and the BTE strategy is still efficacious even in the aged individuals. The improvement of the aged state may promote the repair effect of the BTE in the aged individuals.

Development of a micro-tissue-mediated injectable bone tissue engineering strategy for large segmental bone defect treatment.

BACKGROUND: Bone tissue engineering is not widely used in clinical treatment. Two main reasons hide behind this: (1) the seed cells are difficult to obtain and (2) the process of tissue engineering bone construction is too complex and its efficiency is still relatively low. It is foreseeable that in the near future, the problem of seed cell sources could be solved completely in tissue engineering bone repair. As for the complex process and low efficiency of tissue engineering bone construction, usually two strategies would be considered: (1) the construction strategy based on injectable bone tissue and (2) the construction strategy based on osteogenic cell sheets. However, the application of injectable bone tissue engineering (iBTE) strategy and osteogenic cell sheet strategy is limited and they could hardly be used directly in repairing defects of large segmental bone, especially load-bearing bone. METHODS: In this study, we built an osteogenic micro-tissue with simple construction but with a certain structure and composition. Based on this, we established a new iBTE repair strategy-osteogenic micro-tissue in situ repair strategy, mainly targeting at solving the problem of large segmental bone defect. The steps are as follows: (1) Build the biodegradable three-dimensional scaffold based on the size of the defect site with 3D printing rapid prototyping technology. (2) Implant the three-dimensional scaffold into the defect site. This scaffold is considered as the "steel framework" that could provide both mechanical support and space for bone tissue growth. (3) Inject the osteogenic micro-tissue (i.e., the "cell-extracellular matrix" complex), which could be considered as "concrete," into the three-dimensional scaffold, to promote the bone tissue regeneration in situ. Meanwhile, the digested cells were injected as the compared group in this experiment. After 3 months, the effect of in situ bone defect repair of osteogenic micro-tissue and digested cells was compared. RESULTS: It is confirmed that osteogenic micro-tissue could achieve a higher efficiency on cell usage and has a better repair effect than the digested cells. CONCLUSIONS: Osteogenic micro-tissue repairing strategy would be a more promising clinical strategy to solve the problem of large segmental bone defect.

Stereo matching based on adaptive support-weight approach in RGB vector space.

Gradient similarity is a simple, yet powerful, data descriptor which shows robustness in stereo matching. In this paper, a RGB vector space is defined for stereo matching. Based on the adaptive support-weight approach, a matching algorithm, which uses the pixel gradient similarity, color similarity, and proximity in RGB vector space to compute the corresponding support-weights and dissimilarity measurements, is proposed. The experimental results are evaluated on the Middlebury stereo benchmark, showing that our algorithm outperforms other stereo matching algorithms and the algorithm with gradient similarity can achieve better results in stereo matching.