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El tumor de células gigantes (TCG) constituye un tumor óseo benigno relativamente frecuente. Se caracteriza por ser localmente agresivo y el lugar de presentación más frecuente es a nivel del esqueleto axial (fémur distal o tibia proximal). Hasta la actualidad, existen escasos informes de presentaciones atípicas, como a nivel del esternón. En este informe, se presenta el caso de una paciente mujer de 24 años que presenta tumoración indurada a nivel de la región esternal de crecimiento progresivo asociado a dolor. Los hallazgos radiológicos revelan tumoración osteolítica que tiene como origen el cuerpo del esternón y lo compromete casi en su totalidad. Este se proyecta hacia las partes blandas y llega al plano superficial. Debido a la extensión de la enfermedad y al compromiso extenso en el cuerpo del esternón, se realiza la resección del cuerpo y manubrio esternal. El defecto es reconstruido con malla de polipropileno, barras de titanio, parche de epiplón y autoinjerto de piel; se obtiene una adecuada estabilidad de la caja torácica y resultados estéticos favorables. El caso tiene un adecuado manejo oncológico puesto que la resección es completa con márgenes microscópicos libres (resección R0).
Giant cell tumor (GCT) constitutes a relatively common benign bone tumor, characteri-zed by its local aggressiveness. The most frequent site of occurrence is in the axial ske-leton (distal femur or proximal tibia). To date, there have been few reports of atypical presentations, such as at the level of the sternum. In this report, we present the case of a 24-year-old female patient who presented with an indurated mass in the sternal region, progressively growing and associated with pain. Radiological findings revealed an osteolytic mass originating from the body of the sternum, involving almost its entire extent and projecting into the soft tissues, reaching the superficial plane. Due to the extent of the disease and the extensive involvement of the sternal body, resection of the body and manubrium of the sternum was performed. The surgical defect was reconstructed with polypropylene mesh, titanium bars, an omental patch and a skin graft, achieving adequate stability of the thoracic cage and favorable cosmetic results.
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Humans , Female , Adult , Polypropylenes , Giant Cell Tumor of Bone/surgery , Neoplasms/diagnosis , Peru , Prostheses and Implants , Sternum/surgery , Transplantation, Autologous , Biopsy , Tomography , Diagnosis, DifferentialABSTRACT
Objetivo: Relatar o desenvolvimento de uma tecnologia em saúde num centro de material e esterilização (CME). Método: Trata-se do relato de experiência de discentes de enfermagem com base na sua vivência num hospital de referência em oncologia, nefrologia, transplantes e neurocirurgia, utilizando-se a metodologia do Arco de Maguerez. Resultados: No desenvolvimento da tecnologia em saúde em forma de quadro (checklist de acessórios de limpeza), os discentes trabalharam para solucionar um problema que estava prejudicando a qualidade da limpeza no CME. A tecnologia elaborada teve um olhar minucioso para ser de fácil compreensão e intuitiva, de modo que qualquer profissional pudesse rapidamente entender seu propósito. Conclusão: A técnica aplicada na limpeza manual dos PPS possibilitou aos discentes um olhar diferenciado acerca da importância da atuação da enfer-magem na qualidade desse trabalho, além da relevância das tecnologias em saúde no gerenciamento dos processos de enfermagem. (AU)
Objective: To report the development of a health technology in a sterile processing department (SPD). Method: This is a case report from nur-sing students based on their experience in a reference hospital in oncology, nephrology, transplants, and neurosurgery, using the Maguerez Arch metho-dology. Results: In the development of the health technology in the form of a chart (checklist of cleaning accessories), the students worked to solve a problem that was compromising the cleaning quality at the SPD. The developed technology was carefully considered to be easy to understand and intui-tive, so that any professional could quickly understand its purpose. Conclusions: The technique applied to the manual cleaning of healthcare products allowed students to have a different perspective on the importance of nursing performance in the quality of this work, in addition to the relevance of health technologies in the management of nursing processes. (AU)
Objetivo: Reportar la experiencia del desarrollo de una tecnología para la salud en un Centro de Material y Esterilización (CME). Método: Se trata de un relato de experiencia, basado en la experiencia de estudiantes de enfermería en un hospital de referencia en oncología, nefrología, trasplan-tes y neurocirugía, utilizando la metodología del Arco de Maguerez. Resultados: En el desarrollo de la tecnología para la salud en forma de cuadro (lista de verificación de accesorios de limpieza), los estudiantes trabajaron para solucionar un problema que perjudicaba la calidad de la limpieza en el CME. La tecnología sanitaria elaborada tuvo un enfoque minucioso para que fuera fácil de entender e intuitiva, de modo que cualquier profesional pudiera comprender rápidamente su propósito. Conclusión: La práctica vivida en el hospital a partir de la realidad observada permitió a los estudiantes tomar una mirada diferente sobre la importancia de la actuación de la enfermería en la calidad de la limpieza manual de Productos para la Salud (PPS), además de la relevancia de las tecnologías sanitarias en la gestión de los procesos de enfermería. (AU)
Subject(s)
Patient Safety , Sterile Processing Department , Case Reports , Nursing , Biomedical TechnologyABSTRACT
At present,bronchial arterial chemoembolization(BACE)is a well-established,local minimally-invasive palliative treatment technique for mid-to-advanced primary lung cancer.However,its technical details are still controversial,and it is difficult to standardize each technical detail.Through reviewing the literature,this paper provides a detailed review of BACE,focusing on the source of lung cancer blood supply,embolization materials,particle size of embolization materials,number of treatments,embolization endpoints,selection of anti-tumor drugs,complications,therapeutic effect,etc.(J Intervent Radiol,2024,33:330-334)
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Objective The objective of this study is to improve the accuracy of automatic identification in complex background herbal slice images.The goal is to achieve accurate recognition of herbal slice images in the presence of complex backgrounds.Methods The experiment was conducted on a collected and organized dataset of Tibetan herbal slice images.The RGB,HOG,and LBP features of the slices were analyzed.An improved HOG algorithm was used to fuse multiple features,and a deep learning network was utilized for image recognition.Results The proposed method of multi-feature fusion combined with deep learning achieved an identification accuracy of 91.68%on 3610 Tibetan herbal slice images with complex backgrounds.Furthermore,the average identification accuracy for 20 common traditional Chinese medicine slices,such as Chuan Beimu,Hawthorn,and Pinellia,reached 98.00%.This method outperformed existing methods for identifying herbal slices in complex backgrounds,indicating its feasibility and wide applicability for the identification of other traditional Chinese herbal medicines.Conclusion The fusion of multiple features effectively captures distinguishing characteristics of herbal slices in complex backgrounds.It exhibits high recognition rates for Tibetan herbal slices with complex and heavily occluded backgrounds,and can be successfully applied to the recognition of natural scene-based traditional Chinese herbal medicines and herbal slices.This approach shows promising prospects for practical applications.
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Objective To investigate the feasibility of energy spectrum CT material separation technology for quantitative evaluation of nonalcoholic fatty liver patients,to compare the accuracy of this method with the conventional liver/spleen CT ratio for grading liver fat content.Methods Sixty patients diagnosed with nonalcoholic fatty liver and 20 healthy volunteers were chosen to undergo liver MR multi-echo(ME)Dixon and energy spectrum CT scans.The proton density fat fraction(PDFF),fat concentration(FC),and liver/spleen CT ratio were then measured for each participant.According to PDFF,nonalcoholic fatty liver patients were divided into mild fatty liver group,moderate fatty liver group,and severe fatty liver group.Results With the increase in PDFF,FC increased and the liver/spleen CT ratio decreased.The difference between FC groups in normal,mild,moderate and severe fatty liver groups was statistically significant(P<0.05),while the difference between the liver/spleen CT ratio of normal group and mild fatty liver group was not statistically significant(P>0.05).The receiver operating characteristic(ROC)curve analysis showed that when the critical value of FC was 351.19 mg/mL,the sensitivity,specificity and area under the curve for normal group and fatty liver group were 0.95,0.1 and 0.99,respectively.Conclusion The energy spectrum CT material separation technology has a good correlation between the fat content measured by the MR ME Dixon,which is superior to the fat content measured by the liver/spleen CT ratio.For patients with nonalcoholic fatty liver,FC in energy spectrum CT has high accuracy in differentiating normal and mild fatty liver.
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BACKGROUND:In the treatment of edentulous maxillary implants supported fixed repair,the selection of upper scaffold structure materials and the design of different distal implant implantation methods have a close influence on the long-term stability of the whole mouth implant repair. OBJECTIVE:To comprehensively explore the influence of three different materials of upper scaffold and two implant fixation designs on the biomechanics of the fixed maxillary implant repair based on the three-dimensional finite element method. METHODS:Based on the conical beam CT data of a healthy adult with normal jaws,the Mimics software was used to separate the maxillary and maxillary dentin three-dimensional solid models,and the Geomagic Studio software was used to construct the three-dimensional finite element model of denture with denture implant and fixed maxillary arch combined with specific model parameters.According to the different designs of distal implants in the maxillary posterior region,two scheme models were established.Scheme 1(Design 1)was designed in accordance with the"All-on-4"design used in clinical practice.Two implants were vertically implanted in the bilateral incisor region of the maxilla,and the other two implants were implanted in the bilateral second premolar region at a 30° angle.In scheme 2(Design 2),two implants were vertically implanted in the lateral incisor region of the maxilla,and two short implants were vertically implanted in the posterior region of the maxilla in the bilateral second premolar region.Three materials(titanium,zirconia and polyether ether ketone)were used to assign values to the upper scaffold structure in the two designs,and six different models were obtained.The biomechanical effects of the implant,surrounding bone tissue and the upper scaffold structure were compared and analyzed in the oblique loading direction. RESULTS AND CONCLUSION:(1)The maximum stress peaks of all models were distributed in the neck region around the posterior implant and the cortical bone under the two edentulous implant fixed restoration schemes,regardless of the material of the upper scaffold.(2)Compared with the alternative design of Design 2,which adopted vertical implantation of short implants,Design 1 showed a more ideal stress distribution on the maxilla.(3)The scaffold model constructed by polyether ether ketone material transferred higher stress to the implant and surrounding bone tissue close to the loading zone of the upper jaw bone,followed by titanium and zirconia.As for the support itself,the peak stress of the upper scaffold of polyether ether ketone was significantly lower than that of the zirconia and titanium scaffolds.Zirconia scaffolds were used among the three upper scaffolds to disperse the stress distribution of implant and bone tissue.(4)The results suggest that both designs can be applied to clinical practice.However,from the perspective of biomechanics,the stress distribution of the implant,surrounding bone tissue and upper scaffold in Design 1 is more rational,which is more conducive to the long-term prognosis of fixed implant repair in patients with edentulous jaws.The upper scaffold material has a certain influence on the stress distribution of the implant-bone interface.
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BACKGROUND:With the right bio-inks,3D printing can be used to create replacements for human tissues and organs that work inside the body.In recent years,3D printing technology has developed rapidly and has great application potential in regenerative medicine. OBJECTIVE:To introduce the types of bio-inks for 3D printing,and review the classification,application,advantages and disadvantages of bio-inks,as well as the future vision. METHODS:With"3D printing,biological ink,tissue engineering,hydrogel,synthetic material,cytoactive factor"as search terms,relevant articles published on PubMed and CNKI databases from 2000 to 2022 were searched by computer and finally 83 articles were included for review. RESULTS AND CONCLUSION:3D bioprinting technology has developed rapidly over the past few decades and has received great attention in various fields,including tissue engineering and biomedicine.Compared with the limitations of traditional biological scaffold manufacturing methods in terms of function and structure,3D printing can better simulate the complex structure of biological tissues and has appropriate mechanical,rheological and biological characteristics.Bio-ink is an essential part of 3D printing.Bioscaffolds produced by printing bio-ink prepared by biological materials have great scientific potential and clinical significance in tissue repair and regenerative medicine.The research of the materials itself is also getting more and more attention from experts.Bio-inks for 3D printing come in a variety of materials,from natural to synthetic,to aggregations of cells that do not require any additional biomaterials,and their usefulness in practical use varies.In the future,more and more bio-inks will be developed for tissue engineering.It is necessary to analyze the printability of bio-inks through sufficient experimental simulation and equipment testing to meet the actual medical needs.
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BACKGROUND:Bioactive glass bone repair material has bone-bonding ability,bone induction ability and bone conduction characteristics.However,the performance of bioactive glass does not meet the requirements of clinical application,and the addition of boron is expected to improve the performance of bioactive glass. OBJECTIVE:To study the effect of different contents of B2O3 replacing SiO2 on the mechanical properties and bioactivity of bioactive glass. METHODS:Based on bioactive glass containing phosphorus nitrogen and oxygen(composition:SiO2-CaO-ZnO-Na2O-Si3N4-P2O5),B2O3 was used to partially replace the SiO2.The basic glass containing B2O3 with a mass fraction of 0%(group A),5%(group B),10%(group C),and 15%(group D)was fired using the high-temperature melting method(the total mass fraction of SiO2 and B2O3 in the basic broken glass was 41%).Porous bioactive glass scaffolds were fabricated by the organic foam impregnation method.Uniaxial compression and three-point bending method of universal mechanical testing machine were used to test mechanical properties.Four groups of scaffolds were immersed in simulated body fluids to detect the degradation performance of scaffolds.Scanning electron microscopy was used to observe the morphological changes of scaffolds before and after soaking.X-ray diffraction was used to analyze the phase composition of scaffolds before and after soaking. RESULTS AND CONCLUSION:(1)With the increase of the mass fraction of B2O3,the compressive strength and bending strength of the porous bioactive glass scaffold increased,and there was a significant difference between the compressive strength and bending strength of the four groups(P≤0.05).(2)After soaking in simulated body fluids,the porous bioactive glass scaffolds degraded gradually with the extension of time.At the same soaking time point,the degradation rate of the scaffolds was accelerated with the increase of the mass fraction of B2O3,and the compressive strength and bending strength of the scaffolds in the four groups were significantly different(P≤0.05).(3)Scanning electron microscopy after soaking in simulated body fluids showed that a large number of granular materials were deposited on the surface of group A and group B after soaking for 1 day.After 3 days,the granular materials on the surface fused with each other to form film-like deposits.After 7 days,the films on the surface fused with each other to form pieces,basically covering the entire surface of the specimen.After soaking for 1 day,film-like material deposition was formed on the surface of group C,and after 3 days,the films on the surface were fused into pieces,basically covering the whole surface of the specimen.After soaking for 1 day in group D,flake material covering the whole surface of the specimen could be seen.(4)X-ray diffraction analysis after 1 day of immersion in simulated body fluids showed that the deposits on the surface of the four groups of scaffolds were crystallized hydroxyapatite.(5)B2O3 replacement of SiO2 can enhance the mechanical properties,degradation properties and in vitro mineralization activity of porous bioactive glass scaffolds.
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BACKGROUND:At present,the dental composite resin filling material composed of resin matrix monomer is the first choice material for the filling treatment of dental defects,but with the increase of its use time in the oral environment,the dental tissue will develop secondary caries and the filling material will wear and break.The main cause of these problems is the polymerization shrinkage of the filling material and its mismatch with the mechanical properties of the dental tissue. OBJECTIVE:To synthesize a new type of dental composite resin monomer by adding initiators with different components,to improve the traditional double bond conversion rate of the system and further improve the mechanical properties of the material. METHODS:A new composite resin matrix system was prepared by adding different initiators to the monomer of 3,3′,5,5′-tetramethoxybiphenyl-4,4′-diol epoxy acrylate resin.In group A,camphorquinone with a mass fraction of 1.1%was added.In group B,1-phenyl-1,2-propanedione with a mass fraction of 2.1%was added.In group C,a mixture of camphorquinone and 1-phenyl-1,2-propanedione(a mass ratio of the two was 1:1)with a mass fraction of 3.1%was added.The double bond conversion,polymerization shrinkage and mechanical properties of the samples were determined. RESULTS AND CONCLUSION:(1)The double bond conversion rate of groups B and C was higher than that of group A(P<0.05).The polymerization shrinkage of group B was higher than that of group A(P<0.05),while that of group C was lower than that of group A(P<0.05).(2)The flexural strength,elastic modulus and compressive strength of groups B and C were higher than those of group A(P<0.05,P<0.01).Vickers hardness of group B was higher than that of group A(P<0.05),and the Vickers hardness of group C was lower than that of group A(P<0.01).(3)These findings suggest that 1-phenyl-1,2-propanedione is an initiator with ideal performance.The combined application of 1-phenyl-1,2-propanedione and camphorquinone can effectively improve the double bond conversion rate of the resin matrix system and further improve the mechanical property of the resin.
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BACKGROUND:At present,nanocomposite gelatin methacryloyl hydrogels have been extensively studied in bone tissue engineering. OBJECTIVE:To review the latest research progress of nanocomposite gelatin methacryloyl hydrogels,and introduce the application of nanocomposite gelatin methacryloyl hydrogels in different bone defect environments. METHODS:The computer retrieval was conducted for relevant literature published in CNKI,WanFang,PubMed,and Web of Science databases from 2016 to 2023.The Chinese and English search terms were"gelatin,methacryl*,nano*,bone,bone tissue engineering,bone regeneration,osteogenesis". RESULTS AND CONCLUSION:(1)Up to now,inorganic nanomaterials,organic nanomaterials and organic-inorganic hybrid nanomaterials are the main nanomaterials used as fillers for gelatin methacryloyl.(2)Inorganic nanomaterials enhance the mechanical strength of gelatin methacryloyl,improve its thixotropic properties and degradation rate,and realize the antibacterial,osteogenic,immunoregulatory,angiogenic and other functions of gelatin methacryloyl hydrogel through its surface charge regulation,drug/factor loading,metal ion self-degradation release,etc.(3)Organic nanomaterial and organic-inorganic hybrid nanomaterial composite gelatin methacryloyl hydrogel are two emerging materials.At present,there are relatively few studies,but from the published research,compared with inorganic nanomaterial gelatin methacryloyl hydrogel,organic nanomaterial gelatin methacryloyl hydrogel has better biocompatibility and drug-loading performance.The interaction between nano phase and organic polymer phase is stronger,and the dispersion of nano particles is better.(4)Organic-inorganic hybrid nanomaterial composite gelatin methacryloyl combines the advantages of the previous two,and has better controllability of metal ion release,which proves great research potential.(5)Nanomaterials can enhance the antibacterial,immune regulation,osteogenesis and other biological properties of gelatin methacryloyl,so as to promote bone regeneration in the complex bone defect microenvironment,such as infected bone defect,diabetes,osteosarcoma resection and so on.However,the relevant research of nanocomposite gelatin methacryloyl hydrogel in bone repair is still limited to animal experiments.Further safety testing and clinical studies are still needed.
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BACKGROUND:Bone wax is a filler that can be used for bone hemostasis.Although modification of bone wax formulations is attempted worldwide,its inertness is still the main challenge today.There is an urgent clinical need to develop novel orthopedic hemostatic materials with hemostasis,osteogenesis and antibacterial properties. OBJECTIVE:To review the development of orthopedic hemostatic materials including bone wax and its substitutes. METHODS:PubMed,Web of Science,WanFang,CNKI and VIP databases were searched for literature related to bone wax,hemostatic materials,and research progress of orthopedic hemostatic materials,and 136 articles were selected for inclusion in the review by reading the abstracts of the articles in the initial screening. RESULTS AND CONCLUSION:To replace traditional bone wax,researchers have developed various orthopedic hemostatic materials based on the needs of practical scenarios such as hemostasis and osteogenesis.However,relevant studies mostly focus on basic physical and chemical and performance tests,lack a systematic evaluation system,and lack sufficient reports of large animal experiments and clinical trials.Therefore,bone wax is still a recognized orthopedic hemostatic material at present.The fundamental reason is that the design of existing materials cannot timely meet the new needs of intraoperative hemostasis,postoperative osteogenesis and clinical practice.In the future,the structure,composition and function of existing hemostatic and osteogenic materials need to be integrated and redesigned to meet the increasing demand for hemostatic and osteogenic materials.
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BACKGROUND:At present,plant-derived absorbable hemostats are mainly imported,so it is necessary to develop domestic alternatives that are not inferior to similar imported products. OBJECTIVE:To investigate the hemostatic effect of oxidized regenerated cellulose hemostatic material on a model of minipig liver hemorrhage. METHODS:A total of 24 Bama minipigs were selected and randomly divided into three groups.In the sham operation group(n=6),only an open operation was performed,and the damaged side of the liver was removed and put back in situ.In the experimental group(n=12),the liver hemorrhage model was established,and the oxidized regenerated cellulose hemostatic material was applied to the wound.In the control group(n=6),commercially available absorbable hemostatic gauze was used on the wound after establishing liver hemorrhage models.Hemostatic time and blood loss were recorded.The venous blood of the minipig anterior cavity was collected at different time points before and after modeling,and the blood routine and liver and kidney functions were analyzed.Hematoxylin-eosin staining and Masson staining were performed at 2,6,and 14 weeks after modeling.The main organs were observed by histopathology at 14 weeks after modeling.A liver ultrasound examination was performed at different time points after modeling to observe the degradation and absorption of materials. RESULTS AND CONCLUSION:(1)There was no significant difference in intraoperative hemostatic time and blood loss between the experimental group and the control group(P>0.05).(2)The monitoring results of blood biochemical indexes demonstrated that the levels of aspartate transaminase and glutamic pyruvic transaminase in the three groups were higher 24 hours after modeling than before modeling,and the indexes basically recovered to the normal levels 72 hours after modeling.There were no significant differences in blood biochemical indexes such as liver and kidney functions,blood glucose and inflammatory factors among the three groups(P>0.05).(3)Hematoxylin-eosin staining and Masson staining of histopathology revealed that 2 weeks after surgery,granulation tissue formation and a large amount of collagen fiber deposition were observed on the liver wounds of the two groups,and there were obvious fibrous hyperplasia zones and inflammatory cell infiltration,and the wound healed well.14 weeks after modeling,the liver wounds of two groups of minipigs exhibited mild fibrous hyperplasia zone,collagen fiber deposition and a small amount of inflammatory cell infiltration,complete material degradation,and the healed wound.Hematoxylin-eosin staining showed no significant pathological changes in major organs.(4)Ultrasonic examination demonstrated that the materials of both groups were degraded gradually with the extension of implantation time,and most of them were degraded and absorbed by 56 days after molding.(5)The results confirm that the oxidized regenerated cellulose hemostatic material can effectively prevent liver wound hemorrhage in minipigs,and the hemostats are safe and reliable.
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BACKGROUND:The repair of articular cartilage injury remains a difficult problem to be solved urgently in clinical practice.Utilizing synthetic or biological materials to promote cartilage regeneration has been a research hotspot. OBJECTIVE:To review the research progress of synthetic and biological materials in articular cartilage repair. METHODS:PubMed and CNKI databases were searched for articles about the progress of synthetic and biological materials utilized in articular cartilage repair."Collagen,gelatin,silk,chitosan,alginate,PEG,PCL,PLA,cartilage tissue engineering,cartilage tissue engineering materials"were used as English and Chinese search terms,respectively.After preliminary screening based on the inclusion and exclusion criteria,98 articles with high quality and relevance were retained for review. RESULTS AND CONCLUSION:Natural materials,including collagen,gelatin,silk,chitosan,and alginate,have good biocompatibility and degradability.Synthetic materials,containing polyethylene glycol,polycaprolactone,and polylactic acid,have good mechanical properties.Modification and composition of materials can overcome the inherent defects in materials and show better cartilage repair ability.Studies about multi-layer scaffolds based on hierarchical structure are rare,and it is more targeted at osteochondral injury repair rather than simple cartilage injury repair.At present,scaffold research is focused on the synthetic research and development stage,and the corresponding clinical trials are few,so it is necessary to pay attention to clinical transformation in the future.
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BACKGROUND:Adjustable piezoelectric effect can promote tissue regeneration and repair.Piezoelectric materials are widely used in weight-bearing tissue engineering. OBJECTIVE:To prepare a piezoelectric film material that can promote bone regeneration,and to explore its structural characterization,electrical output performance,biocompatibility,and effect of electrical output on osteogenic differentiation of rabbit bone marrow mesenchymal stem cells. METHODS:Using poly-3-hydroxybutyrateco/4-hydroxybutyrate(P34HB)as raw material,barium calcium stannate titanate powder(Ba0.94Ca0.06Sn0.08Ti0.92O3,BCST)was added according to mass ratios of 0%,5%,10%,15%,and 20%.Dichloromethane was added to solve P34HB,and the thickness of 150-200 μm BCST/P34HB piezoelectric film was prepared by vacuum drying method.After polarization in the oil bath,the surface morphology,crystal phase composition,piezoelectric coefficient and open circuit voltage were tested.The effect of BCST/P34HB electrical output at 110 Hz and 0.25 N force on the proliferation and osteogenic differentiation of rabbit bone marrow mesenchymal stem cells was tested. RESULTS AND CONCLUSION:(1)Scanning electron microscopy,X-ray diffraction,water contact angle,piezoelectric coefficient and electrical output performance tests showed that when the mass ratio of BCST increased to 20%,the BCST/P34HB piezoelectric film had good piezoelectric properties(d33=5.9 pC/N)and electrical output performance(180 mV),which was closer to the suitable range of 500 mV for electrical stimulation.(2)Live and dead staining showed that on the first day of co-culture,15%group and 20%group showed less red fluorescence.On the 5th day of culture,the number of green fluorescence in each group was significantly higher than that on the first day,and the red fluorescence was not observed in the 10%,15%and 20%groups,and only a small amount of red fluorescence was observed in the 0%and 5%groups.(3)On the 1st,3rd and 5th days of co-culture with rabbit bone marrow mesenchymal stem cells,Almar blue staining exhibited that the number of cells in each group showed an increasing trend with the increase of time.On the 5th day of culture,the number of cells in the 20%group was significantly more than that in the 0%group(P<0.05).(4)On day 10 of osteogenic induction,alkaline phosphatase staining results showed that the positive rate of the 20%group was significantly higher than that of the 0%group(P=0.000 1).On day 21,alizarin red staining and quantitative analysis of calcium nodules showed a similar trend to alkaline phosphatase staining.Compared with the 0%group,the 15%group and 20%group showed significant differences(P<0.01,P<0.000 1).(5)The results showed that 20%BCST/P34HB films had good piezoelectric properties,electrical output properties,biocompatibility and the ability of promoting osteogenic differentiation of bone marrow mesenchymal stem cells.
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BACKGROUND:Material biomechanics is the investigation of the mechanical microenvironment of biomaterials through a material science approach,which belongs to the frontier discipline of sustainable development. OBJECTIVE:To explore the current research hotspots and development trends of material biomechanics and provide theoretical references for subsequent research. METHODS:Based on CiteSpace bibliometric software,we generated keyword co-occurrence and clustering,emergent word detection,and other knowledge maps based on 3 182 material biomechanics literature in the Web of Science core database during 2012-2022 for visualization analysis. RESULTS AND CONCLUSION:The number of research articles on the biomechanics of materials has been increasing in the last decade,and the United States,China,and Germany are the top three countries in terms of the number of articles published,and the research is mainly concentrated on major universities and research institutions,with significant aggregation.Material biomechanics research mainly involves the disciplines of material science,biomedical engineering,and kinesiology.Finite element analysis,material properties,mechanical performance of biomaterials,and molecular biomechanics are the focus of scholars'attention and research.At present,the research in the field of material biomechanics focuses on the use of finite element analysis to calculate the mechanical response of different biomedical materials under different conditions of loading and mechanical properties for the prevention of sports diseases,surgical planning,and postoperative rehabilitation.The application of inorganic materials and the mode of transport of molecular signals may be the prospect of future research.
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BACKGROUND:Scaffold materials serve as platforms that provide space and structure,playing a crucial role in the regeneration of cartilage tissue.Scholars from around the world are exploring different approaches to fabricate more ideal scaffold materials. OBJECTIVE:To review the design principles and preparation methods of cartilage scaffolds,and to further explore the advantages and limitations of various preparation methods. METHODS:Literature searches were conducted on the databases of CNKI,WanFang Data,PubMed,and FMRS from 1998 to 2023.The search terms were"cartilage repair,cartilage tissue engineering,cartilage scaffold materials,preparation"in Chinese and English.A total of 57 articles were ultimately reviewed. RESULTS AND CONCLUSION:(1)The articular cartilage has a unique structure and limited self-repair capacity after injury.Even if self-repair occurs,the newly formed cartilage is typically fibrocartilage,which is far inferior to normal articular cartilage in terms of structure and mechanical properties.It is difficult to maintain normal function and often leads to degenerative changes.Currently,the design and fabrication of scaffold materials for cartilage repair need to consider the following aspects:biocompatibility and biodegradability,suitable pore structure and porosity,appropriate mechanical properties,and bioactivity.(2)Research on the preparation of cartilage scaffolds has made significant progress,continuously introducing new preparation methods and optimization strategies.These methods have their advantages and disadvantages,providing more possibilities for customized preparation and functional design of cartilage scaffolds according to specific requirements.
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BACKGROUND:Although nerve conduits provide an effective treatment approach for nerve repair,traditional nerve conduits merely serve as mechanical channels in the repair process.The therapeutic effect still needs to be improved.Carbon nanomaterials have good physicochemical properties and hold great potential in fields such as electrochemistry and tissue engineering.Nerve conduits loaded with carbon nanomaterials,after appropriate functional modifications,are expected to further enhance the quality of nerve repair. OBJECTIVE:To review the recent research progress of carbon nanomaterial-loaded nerve conduits/scaffolds for peripheral nerve repair. METHODS:PubMed,Web of Science,China National Knowledge Infrastructure(CNKI),and Wanfang databases were searched for the literature on the application of carbon nanomaterial catheters in peripheral nerve regeneration.English keywords were"carbon nanomaterials,carbon-based nanomaterials,nerve conduit,nerve guidance conduit,scaffold,nerve regeneration,peripheral nerve repair,peripheral nerve injury"and Chinese keywords were"carbon nanomaterials,carbon materials,graphene,carbon nanotubes,nerve conduits,nerve scaffolds,nerve repair,nerve regeneration,peripheral nerve injury".Finally,69 articles were selected for this review. RESULTS AND CONCLUSION:(1)Carbon nanomaterials primarily restore damaged neural bioelectric signal conduction by activating calcium ion channels and inducing intracellular calcium activity.The application of various nerve conduit design strategies has improved the effectiveness of nerve repair.(2)Successful intraneural vascularization is the prerequisite for repairing peripheral nerve injuries.Reactive oxygen species and reactive nitrogen species generated by carbon nanomaterials trigger subsequent signaling pathways that promote intraneural vascularization.(3)The ratio of M1 to M2 macrophages affects the repair of peripheral nerve injuries.Carbon nanomaterials promote the polarization of macrophages into the M2 phenotype,thereby exerting their anti-inflammatory and regenerative effects.(4)Some carbon nanomaterials may induce excessive generation of reactive oxygen species intracellularly,potentially exhibiting cytotoxicity detrimental to nerve repair.However,appropriate functional modifications can improve the adverse effects caused by carbon nanomaterials.(5)Although carbon nanomaterials can restore the microenvironment of peripheral nerve injuries and play a positive role in promoting peripheral nerve regeneration,their inherent cytotoxicity and unclear in vivo degradation pathways still pose challenges for clinical application.However,by employing methods such as functional modification,it is possible to enhance the biocompatibility of carbon nanomaterials.Modified carbon nanomaterials have promising prospects in the field of neural tissue engineering.
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BACKGROUND:Bone is a remarkable natural material possessing piezoelectric properties.By harnessing the biomimetic piezoelectric effect,tissue engineering materials can be employed to effectively address bone tissue defects and facilitate their repair. OBJECTIVE:Using a solid-phase force chemistry technique,a piezoelectric scaffold with inherent osteogenic properties was meticulously fabricated.This unique scaffold was then assessed for its impact on osteoblast adhesion,proliferation,and osteogenic differentiation. METHODS:Polyvinylidene fluoride(PVDF)powders,along with commercially available NaCl(mass ratios are 60:40,50:50,40:60,and 30:70,respectively),were subjected to solid-phase shear milling technology,resulting in a homogenous mixture.Through a melting process,a substantial material was formed,and subsequent treatment with a pure water solution effectively eliminated the NaCl.Consequently,PVDF piezoelectric foam scaffolds with varying pore sizes were successfully prepared.These materials were categorized as PVDF-40,PVDF-50,PVDF-60,and PVDF-70,denoting the respective mass percentages of NaCl during preparation.The surface morphology,crystal phase composition,thermodynamic behavior,mechanical properties,and piezoelectric properties of each group were meticulously characterized.The four kinds of piezoelectric foam scaffolds were co-cultured with the MG63 osteoblast cell line to evaluate its biocompatibility and potential to promote bone differentiation. RESULTS AND CONCLUSION:(1)The scanning electron microscopy,four groups of scaffolds had multi-level pores.As the NaCl mass fraction in the mixed powder increased,the porosity of the scaffolds increased.X-ray energy dispersion spectrum,X-ray diffraction,Fourier transform infrared spectroscopy,and thermogravimetric analysis collectively revealed the scaffold predominantly comprised the α phase,which inherently lacked piezoelectric properties.However,the application of solid-phase force chemistry successfully stimulated the formation of the β phase,thereby enhancing the scaffold's piezoelectric properties.Notably,the PVDF-60 group exhibited the highest proportion of the β phase among all the tested groups.The results of cyclic compression testing and piezoelectric performance assessment demonstrated that the PVDF-60 group exhibited superior compressive strength and piezoelectric performance compared to the other groups.(2)The findings from scanning electron microscopy and laser confocal microscopy exhibited that MG63 cells adhered well to the surface of the four groups of scaffolds,with good morphology,extended more pseudopods,and secreted a large amount of extracellular matrix.CCK-8 assay revealed that the proliferative absorbance of PVDF-60 cells cultured for 4 days was higher than that of the other three groups(P<0.000 1).Alkaline phosphatase staining and alizarin red staining showed that the expression of alkaline phosphatase and the number of calcified nodules in the PVDF-60 group were higher than those in the other three groups(P<0.01,P<0.000 1).(3)The piezoelectric PVDF foam-based scaffolds demonstrated favorable cytocompatibility.Notably,the PVDF-60 group showed superior mechanical properties,piezoelectric performance,and bone-inducing capabilities.
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BACKGROUND:Graphene is the thinnest,strongest,and toughest type of two-dimensional new crystal material,demonstrating significant advantages in biomedical applications.Angiogenesis and vascularization of bone are key factors in tissue repair and regeneration,and are effective ways to address vascular and osteogenic issues. OBJECTIVE:To review the characteristics and mechanisms of graphene and its derivatives in promoting angiogenesis activity and vascularizing bone,in order to provide a reference for their clinical application in vascular tissue repair and regeneration. METHODS:Using a computer to search for relevant literature included in PubMed,ScienceDirect,CNKI,and Wanfang databases,the Chinese search terms were"grapheme","angiogenesis,vascularization","vascularized bone",and"endothelial cells",while the English search terms were"graphene""angiogenesis OR vascularization""vascularized bone""endothelial cells".After excluding literature unrelated to the topic of the article,according to the inclusion and exclusion criteria,62 articles were ultimately included for result analysis. RESULTS AND CONCLUSION:(1)At present,graphene oxide has been studied more and is the most widely used in graphene and its derivatives.(2)Graphene and its derivatives are suitable for heart,bone,nerve,and wound healing related diseases.(3)Graphene and its derivatives have excellent physical and chemical properties and biological properties,but they have potential cytotoxicity.We should pay attention to its biological safety in application.(4)The application of graphene and its derivatives requires further research to demonstrate the optimal size and concentration and measures to reduce toxicity.(5)On the cellular level,graphene and its derivatives can promote angiogenic activity by tip endothelial cell phenotype,mesenchymal stem cell adhesion and proliferation, and vascular smooth muscle cell growth.(6)On the molecular level,graphene and its derivatives can increase the expression of vascular endothelial growth factor,basic fibroblast growth factor,hepatocyte growth factor and activate reactive oxygen species/nitric oxide synthase/nitric oxide signaling pathway,lysophosphatilate R6/Hippo-YAP pathway,stromal cell-derived factor-1/vascular endothelial growth factor and ZEB 1/Notch1 pathway.(7)Grapheme oxide and graphene oxide-copper phosphorylated extracellular regulatory protein kinase and activated hypoxia-inducible factor-1,thereby promoting the up-regulation of vascular endothelial growth factor and bone morphogenetic protein-2 expression,and promoting angiogenesis and vascularized bone.(8)In summary,graphene and its derivatives,especially graphene oxide,have great application prospects in the repair and regeneration of vascularized tissues due to their excellent biological properties,good angiogenesis and vascularized bone ability.
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BACKGROUND:The combination of machine learning and medical metal materials can make up for the inefficiency and high cost of traditional experiments and computational simulations,and quickly and accurately predict the characteristics of metal materials by analyzing large amounts of data,optimize material design and performance,and improve the safety and efficiency of medical applications. OBJECTIVE:To summarize the research progress and shortcomings of machine learning in the characteristics of medical materials. METHODS:The first author searched CNKI,PubMed,X-MOL,and Web of Science databases by computer to search all relevant articles from January 2013 to April 2023.The Chinese search terms were"machine learning of medical metal materials,medical titanium alloy,medical magnesium alloy,medical metal material properties".The English search terms were"machine learning medical metal materials,medical stainless steel alloy,medical cobalt-chromium alloy,medical titanium alloy,medical magnesium alloy".Finally,70 relevant articles were included for a summary. RESULTS AND CONCLUSION:(1)The introduction of machine learning as a material design methodology has opened up new paradigms for material science research as the accessibility of large amounts of data generated by traditional experimental and computational simulation methods increases.(2)The machine learning workflow is divided into four main parts:data collection and preprocessing,feature engineering,model selection and training,and model evaluation,each of which is indispensable.(3)Medical metal materials are categorized into:stainless steel co-base alloys,cobalt-chromium alloys,titanium alloys,and magnesium alloys.For stainless steel co-base alloy,machine learning predicts its mechanical properties,to improve the generalization ability of machine learning.For cobalt-chromium alloy,machine learning predicts its mechanical properties,and it can conclude that cobalt-chromium alloy is the optimal material for hip implants.For titanium alloy,machine learning predicts its mechanical properties,and it can select the implant with the best mechanical properties.For magnesium alloy,machine learning predicts its corrosion resistance and mechanical properties;the ensemble model can accurately predict the mechanical properties of magnesium alloys,and the random forest model can predict the optimal elemental contents of magnesium alloys as vascular stents.(4)Machine learning has deficiencies in the field of medical materials.For example,the model is relatively lagging;the data failed to be standardized,and the generalization is low.To solve such problems,we should make full use of deep learning and segmentation algorithm technology,use unified standard data,and improve the model to increase the generalization ability.