OBJECTIVE: To review and summarize the research progress on repairing segmental bone defects using three-dimensional (3D)-printed bone scaffolds combined with vascularized tissue flaps in recent years. METHODS: Relevant literature was reviewed to summarize the application of 3D printing technology in artificial bone scaffolds made from different biomaterials, as well as methods for repairing segmental bone defects by combining these scaffolds with various vascularized tissue flaps. RESULTS: The combination of 3D-printed artificial bone scaffolds with different vascularized tissue flaps has provided new strategies for repairing segmental bone defects. 3D-printed artificial bone scaffolds include 3D-printed polymer scaffolds, bio-ceramic scaffolds, and metal scaffolds. When these scaffolds of different materials are combined with vascularized tissue flaps ( e.g., omental flaps, fascial flaps, periosteal flaps, muscular flaps, and bone flaps), they provide blood supply to the inorganic artificial bone scaffolds. After implantation into the defect site, the scaffolds not only achieve structural filling and mechanical support for the bone defect area, but also promote osteogenesis and vascular regeneration. Additionally, the mechanical properties, porous structure, and biocompatibility of the 3D-printed scaffold materials are key factors influencing their osteogenic efficiency. Furthermore, loading the scaffolds with active components such as osteogenic cells and growth factors can synergistically enhance bone defect healing and vascularization processes. CONCLUSION The repair of segmental bone defects using 3D-printed artificial bone scaffolds combined with vascularized tissue flap transplantation integrates material science technologies with surgical therapeutic approaches, which will significantly improve the clinical treatment outcomes of segmental bone defect repair.
Printing, Three-Dimensional ; Tissue Scaffolds ; Humans ; Surgical Flaps/blood supply* ; Tissue Engineering/methods* ; Plastic Surgery Procedures/methods* ; Bone and Bones/surgery* ; Biocompatible Materials ; Bone Regeneration ; Bone Transplantation/methods* ; Bone Substitutes ; Osteogenesis

Permanent magnet motor has been widely used in the field of artificial heart pump due to its high power density, high stability and easy control. In this paper, the development history and research progress of permanent magnet motor for blood pump were described. Firstly, the motors were classified according to their structures and application scenarios. And then, the measures taken by different types of motors to meet the corresponding performance requirements were introduced, and the specific application cases were given. After that, commonly used control algorithms of these motors were enumerated. What's more, the advantages and disadvantages of the control algorithms and their application emphasis were carefully explained. Finally, the paper was summarized in short.
Algorithms ; Blood Substitutes ; Heart, Artificial ; Magnetics ; Magnets ; Prosthesis Design

PURPOSE: The purpose of this study was to evaluate the synergistic effect of adjunctive hyperbaric oxygen (HBO) therapy on new bone formation and angiogenesis after 8 weeks of healing. METHODS: Sprague-Dawley rats (n=28) were split into 2 groups according to the application of adjunctive HBO therapy: a group that received HBO therapy (HBO group [n=14]) and another group that did not receive HBO therapy (NHBO group [n=14]). Each group was divided into 2 subgroups according to the type of bone graft material: a biphasic calcium phosphate (BCP) subgroup and an Escherichia coli-derived recombinant human bone morphogenetic protein-2-/epigallocatechin-3-gallate-coated BCP (mBCP) subgroup. Two identical circular defects with a 6-mm diameter were made in the right and left parietal bones of each rat. One defect was grafted with bone graft material (BCP or mBCP). The other defect was not grafted. The HBO group received 2 weeks of adjunctive HBO therapy (1 hour, 5 times a week). The rats were euthanized 8 weeks after surgery. The specimens were prepared for histologic analysis. RESULTS: New bone (%) was higher in the NHBO-mBCP group than in the NHBO-BCP and control groups (P<0.05). Blood vessel count (%) and vascular endothelial growth factor staining (%) were higher in the HBO-mBCP group than in the NHBO-mBCP group (P<0.05). CONCLUSIONS: HBO therapy did not have a positive influence on bone formation irrespective of the type of bone graft material applied after 8 weeks of healing. HBO therapy had a positive effect on angiogenic activity.
Animals ; Blood Vessels ; Bone Morphogenetic Protein 2 ; Bone Substitutes ; Calcium ; Escherichia ; Humans ; Hyperbaric Oxygenation ; Osteogenesis ; Oxygen ; Parietal Bone ; Rats ; Rats, Sprague-Dawley ; Transplants ; Vascular Endothelial Growth Factor A

This study investigated the effect of epigallocatechin-3-gallate (EGCG)-loaded microporous β-tricalcium phosphate (β-TCP) bone substitute in the bone healing of rabbit calvarial defects. New bone formation induced by β-TCP incorporating two different dose of EGCG [1 mg EGCG/200 mg β-TCP (TCP-1), 10 mg EGCG/200 mg β-TCP (TCP-10)] was compared with unloaded β-TCP (TCP-0). Calvarial defects 8 mm diameter created in 14 adult male New Zealand White rabbits were filled with three types of bone substitutes. The amount of newly formed bone was evaluated histomorphometrically at 4 and 8 weeks after implantation. The TCP-1 group exhibited increased bone healing capacity and numerous blood vessel formation compared with the other two groups. New bone formation was observed in the cental area of TCP-1 filled defects at 8 weeks. Histomorphometric analysis revealed significantly greater newly formed bone area in the TCP-1 group when compared with unloaded TCP-0 (p < 0.05 at 4 and 8 weeks) and 10 mg EGCG-loaded TCP-10 groups (p < 0.05 at 8 weeks). No difference was observed in new bone area between TCP-0 and TCP-10 groups. These results suggest that local delivery of 1 mg EGCG to β-TCP bone substitute by simple adsorption promotes bone regeneration in the healing of rabbit calvarial osseous defect and higher EGCG dose (in this study, 10 mg per defect) does not exert any positive effect on bone healing capacity of β-TCP. Thus, local delivery of EGCG to β-TCP bone substitute seems to be an effective approach for the treatment of osseous defects.
Adsorption ; Adult ; Blood Vessels ; Bone Regeneration ; Bone Substitutes ; Humans ; Male ; Osteogenesis ; Rabbits

Platelet-rich fibrin (PRF) has been used in regenerative medicine and dentistry. Recently, its use has been advocated for regenerative periodontics and wound healing. The randomized control trials have assessed the regenerative efficacy of the PRF for restoring intrabony periodontal defects.The objectives are to critically analyze and appraise the currently available literature, focusing on the use of PRF in regenerating periodontal bone defects. An electronic search was conducted (PubMed/MEDLINE, Google Scholar, ISI-WOS). Various combinations of following keywords were used: ‘ platelet-rich fibrin’, ‘ intrabony’, ‘ periodontal’, ‘ bone defect’ and ‘ guided tissue regeneration’.Asecondary search was conducted by analyzing the reference lists of the articles obtained in initial search. The final search resulted in 13 randomized controlled trials being included. Inmajority of studies, PRF resulted in better clinical/radiographic outcomes than open flap debridement and augmented therapeutic effects of bone grafts. The combination of bovine bone substitutes and PRF resulted in better performance compared to alone. Similarly better outcomes were observed while using PRF in combination with nanohydroxyapatite, metformin and demineralized freeze-dried bone allograft. It can be concluded that PRF produces better outcomes than open flap debridement alone and augments the regenerative effects of bone substitutes.
Allografts ; Blood Platelets* ; Bone Substitutes ; Debridement ; Dentistry ; Fibrin* ; Metformin ; Periodontics ; Regeneration ; Regenerative Medicine ; Therapeutic Uses ; Tissue Engineering ; Transplants ; Wound Healing

Blood transfusion is a well-established cell therapy. However, blood available for transfusion is a limited resource and is available only through donations by healthy volunteers. Moreover, the perpetual and widespread shortage of blood products, problems related to transfusion transmitted infections, and new emerging pathogens have elicited an increase in demand for artificial blood. Therefore, research for alternative RBC substitutes has begun in the 1960s. Hemoglobin-based oxygen carriers (HBOC) and perfluorocarbon-based oxygen carrier (PBOC) were two popular study subjects; however, research on these substitute candidates was halted due to unsatisfactory results and safety issues, including death, in the 1990s. Since then, worldwide efforts to produce RBC have shifted over to stem cell-derived RBC production using cord blood and G-CSF-mobilized peripheral blood stem cells, and some progress has been made. In terms of practical usefulness, however, large-scale production and cost effectiveness are still problematic. Recently, human embryonic stem cells (hESC) and human-induced pluripotent stem cells (hiPSC) have shown the potential to produce RBCs as unlimited cell sources. These two methods using hESCs and hiPSCs are also cost-effective since autologous and O, D negative blood RBCs will be used for alloimmunized patients with multiple alloantibodies or rare blood types (high incidence antigens) as well as universal blood production. We will review the current research on in vitro RBC production from hematopoietic stem cells and pluripotent stem cells and assess future directions in this field.
Blood Substitutes ; Blood Transfusion ; Cell- and Tissue-Based Therapy ; Cost-Benefit Analysis ; Erythrocytes* ; Fetal Blood ; Healthy Volunteers ; Hematopoietic Stem Cells ; Human Embryonic Stem Cells ; Humans ; In Vitro Techniques ; Incidence ; Induced Pluripotent Stem Cells ; Isoantibodies ; Oxygen ; Pluripotent Stem Cells ; Stem Cells*

PURPOSE: Lumbar fusion surgery was performed on transfusion-free patients and hemodynamic changes were analyzed. MATERIALS AND METHODS: A total of 36 transfusion-free patients who had undergone lumbar fusion surgery using recombinant human erythropoietin (rHuEPO) before surgery from April 2007 to March 2014 were included in the study. Hemoglobin and hematocrit levels were measured before surgery, immediately after surgery, 12 hours after surgery, on day 1, day 2, day 3, and day 7. Changes in levels were investigated and the factors affecting the changes in hemoglobin levels were analyzed. RESULTS: Changes in hemoglobin and hematocrit were -18.11% before surgery and -22.92% on day 7, respectively, and they tended to recover from day 2 after surgery. Depending on the patient's age, gender, body mass index, blood loss, and surgery method (presence of lumbar interbody fusion), the changes in hemoglobin level did not show statistically significant differences; however, significant differences were observed in the surgical time and extent of the operation. CONCLUSION: Transfusion alternatives during lumbar spinal fusion are deemed safe methods, leading to good, postoperative hemodynamic outcomes. However, the surgical time and extent of the operation must be determined before surgery.
Blood Substitutes ; Blood Transfusion* ; Body Mass Index ; Erythropoietin ; Hematocrit ; Hemodynamics* ; Humans ; Methods ; Operative Time ; Spinal Fusion ; Spine*

α-Gal, the main xenotransplantation antigen, can lead to hyperacute rejection (HAR) in xenotransplantation. This study was purposed to investigate the effect of recombinant α-galactosidase (α-Gal antigen) on the Holstein-Friesian(H-F) red blood cells (RBC). The enzymelysis method was used to digest the α-Gal antigen on H-F RBC; the saline and anti-human globulin methods were used to perform the agglutination test of H-F RBC and human plasma; the flow cytometry was used to detect the α-Gal antigen on surface of H-F RBC, fluorescence intensity of FITC-IB4 and FITC-IgG labeled RBC. The results indicated that the saline and anti-human globulin method showed α-galactosidase-treated H-F RBC fail to agglutinate with human pooled plasma; the flow cytometry showed the fluorescence intensity of FITC-IB4 and FITC-IgG labeled RBC decrease 99.0% and 87.8%, respectively. It is concluded that the novel α-galactosidase can be used to cleared the α-Gal antigen on the surface of H-F RBC and α-galactosidase-treated H-F RBC may be considered as human blood substitute.
Animals ; Blood Substitutes ; Cattle ; Erythrocytes ; immunology ; Female ; Humans ; Transplantation, Heterologous

To date, the use of red blood cells (RBCs) produced from stem cells in vitro has not proved practical for routine transfusion. However, the perpetual and widespread shortage of blood products, problems related to transfusion-transmitted infections, and new emerging pathogens elicit an increasing demand for artificial blood. Worldwide efforts to achieve the goal of RBC production through stem cell research have received vast attention; however, problems with large-scale production and cost effectiveness have yet to prove practical usefulness. Some progress has been made, though, as cord blood stem cells and embryonic stem cells have shown an ability to differentiate and proliferate, and induced pluripotent stem cells have been shown to be an unlimited source for RBC production. However, transfusion of stem cell-derived RBCs still presents a number of challenges to overcome. This paper will summarize an up to date account of research and advances in stem cell-derived RBCs, delineate our laboratory protocol in producing RBCs from cord blood, and introduce the technological developments and limitations to current RBC production practices.
Blood Substitutes ; Cost-Benefit Analysis ; Embryonic Stem Cells ; Erythrocytes* ; Fetal Blood ; Induced Pluripotent Stem Cells ; Stem Cell Research ; Stem Cells*

The term "endo-perio" lesion has been proposed to describe the destructive lesion resulting from inflammatory products found in varying degrees in both the periodontium and the pulpal tissues. In most of the cases, clinical symptoms disappear following successful endodontic therapy. However failure after conventional root canal treatment calls for surgical intervention. A 35 year old male patient with endo-perio lesion in right maxillary lateral incisor was treated with platelet rich fibrin (PRF) and alloplastic bone substitute after conventional endodontic therapy. At the end of 6 months there was gain in clinical attachment, increased radiographic bone fill and reduction in probing depth which was maintained till 18 month follow-up. Present case report aims to evaluate the efficacy of PRF and alloplastic bone substitute in the management of intrabony defect associated with endo-perio lesion in maxillary lateral incisor because the healing potential of PRF and bone graft has not been widely studied in endodontics. The use of PRF allows the clinician to optimize tissue remodelling, wound healing and angiogenesis by the local delivery of growth factors and proteins. The novel technique described here enables the clinician to be benefited from the full regenerative capacity of this autologous biologic material.
Blood Platelets* ; Bone Regeneration ; Bone Substitutes* ; Dental Pulp Cavity ; Endodontics ; Fibrin* ; Follow-Up Studies ; Humans ; Incisor ; Intercellular Signaling Peptides and Proteins ; Male ; Periodontium ; Transplants ; Wound Healing