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La enseñanza de chino es un pilar importante para mantener la unidad de la comunidad china de ultramar, perpetuar la cultura étnica tradicional, así como contar la historia china y difundir la voz china en las sociedades chinas de ultramar. El 2 de agosto de 2022, la reunión temática sobre “La Enseñanza de Chino en América Latina” tuvo lugar en la Universidad Suroeste de Ciencia y Tecnología. Esta es el tercer encuentro de la serie de “Simposios de Estudios Chinos de Ultramar en América Latina”. La reunión invitó a expertos y académicos de los ámbitos pertinentes, representantes de chinos de ultramar y educadores de chino para intercambiar opiniones sobre la historia, la situación actual y el futuro modelo de desarrollo de la enseñanza de chino en América Latina y el Caribe. Esperamos que a través de esta reunión temática, se permite explorar un camino sostenible para el futuro desarrollo de la enseñanza de chino en América Latina. Hemos traducido y editado las actas de la reunión en este trabajo, con el fin de servir de referencia a más investigadores de esta área relacionada y ayudar a los departamentos relevantes en la formulación de políticas.

Polymeric biocomposites display some advantages over metal or ceramic biomaterials, and are regarded as a promising candidate for artificial joint application. Herein, molybdenum disulfide (MD) nanosheets were prepared and incorporated into polyimide (PI) to form MD/PI composites with a MD content of 20 wt% (PM20) and 40 wt% (PM40). The results revealed that incorporation of MD nanosheets obviously improved the tribological performances, surface properties (

As an implantable biomaterial, polyetherketoneketone (PEKK) exhibits good mechanical strength but it is biologically inert while tantalum (Ta) possesses outstanding osteogenic bioactivity but has a high density and elastic modulus. Also, silicon nitride (SN) has osteogenic and antibacterial activity. In this study, a microporous surface containing both SN and Ta microparticles on PEKK (STP) exhibiting excellent osteogenic and antibacterial activity was created by sulfonation. Compared with sulfonated PEKK (SPK) without microparticles, the surface properties (roughness, surface energy, hydrophilicity and protein adsorption) of STP significantly increased due to the SN and Ta particles presence on the microporous surface. In addition, STP also exhibited outstanding antibacterial activity, which inhibited bacterial growth in vitro and prevented bacterial infection in vivo because of the presence of SN particles. Moreover, the microporous surface of STP containing both SN and Ta particles remarkably induced response (e.g., proliferation and differentiation) of rat bone mesenchymal stem (rBMS) cells in vitro. Furthermore, STP significantly improved new bone regeneration and osseointegration in vivo. Regarding the induction of cellular response in vitro and improvement of osseointegration in vivo, the microporous surface containing Ta was better than the surface with SN particles. In conclusion, STP with optimized surface properties activated cellular responses in vitro, enhanced osseointegration and prevented infection in vivo. Therefore, STP possessed the dual biofunctions of excellent osteogenic and antibacterial activity, showing great potential as a bone substitute., Graphical abstract Image 1, Highlights •Microporous surface containing SN/Ta microparticles on PEKK (STP) was created. •Surface performances (e.g., roughness) of STP were significantly increased. •STP exhibited antibacterial activity in vitro and prevented infection in vivo. •STP remarkably induced response of bone mesenchymal stem cells in vitro. •STP obviously improved bone regeneration and osseointegration in vivo.

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) (eg, gefitinib) exert potent therapeutic efficacy in non–small‐cell lung cancer (NSCLC) harboring EGFR‐activating mutations. However, the resistance to EGFR TKIs limits their clinical therapeutic efficacy. TIP30, a newly identified tumor suppressor, appears to be involved in the regulation of cytoplasmic and nuclear EGFR signaling in NSCLC. Our previous study demonstrated that TIP30 regulated EGF‐dependent cyclin D1 transcription in human lung adenocarcinoma and suppressed tumorigenesis. In the present study, the involvement of TIP30 in combating gefitinib resistance in NSCLC was determined for the first time in vitro and in vivo. Gain and loss of function studies showed that overexpression of TIP30 effectively sensitized cells to gefitinib in vitro, whereas TIP30 inhibition promoted gefitinib cell resistance. Moreover, TIP30 negatively regulated the activation of the p‐AKT and p‐MEK signaling pathways in PC9/GR. Importantly, PC9/GR harbored high levels of nuclear EGFR, and overexpression of TIP30 restored irregular EGFR trafficking and degradation from early endosomes to the late endosomes, decreasing the nuclear accumulation of EGFR, which may partly or totally inhibit EGFR‐mediated induction of c‐Myc transcription. Xenographic tumors induced by overexpression of TIP30 by PC9/GR cells in nude mice were suppressed compared with their original counterparts. Overall, it was revealed that TIP30 overexpression restored gefitinib sensitivity in NSCLC cells and attenuated the cytoplasmic and nuclear EGFR signaling pathways and may be a promising biomarker in gefitinib resistance in NSCLC., This work investigated the vital role of TIP30 in gefitinib resistance of NSCLC‐involved modulation of the nuclear EGFR signaling pathway. Findings indicated that a low TIP30 level may confer gefitinib resistance and overexpression of TIP30 may predict a favorable response to gefitinib‐based chemotherapy in NSCLC.

Implanted materials with both osteogenic and antibacterial functions are promising for facilitating osteointegration and preventing infection for orthopedic applications. In this work, we synthesized flower-like molybdenum disulfide (fMD) submicro-spheres containing nanosheets, which were incorporated onto the microporous surface of polyimide (PI)

Dong Xie,1,2,* Chenhui Xu,1,* Cheng Ye,1,* Shiqi Mei,3 Longqing Wang,1 Qi Zhu,1 Qing Chen,1 Qi Zhao,1 Zhiyan Xu,3 Jie Wei,3 Lili Yang1 1Spine Center, Department of Orthopaedics, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, 200003, People’s Republic of China; 2Department of Orthopaedics, PLA Navy No.905 Hospital, Shanghai, 200052, People’s Republic of China; 3Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, 200237, People’s Republic of China*These authors contributed equally to this workCorrespondence: Lili Yang Tel +86-021-81885793Email yangll@smmu.edu.cnPurpose: Polyetheretherketone (PEEK) exhibits high mechanical strengths and outstanding biocompatibility but biological inertness that does not excite the cell responses and stimulate bone formation. The objective of this study was to construct submicro-nano structures on PEEK by femtosecond laser (FSL) for exciting the responses of MC3T3-E1 cells and gingival epithelial (GE) cells, which induce regeneration of bone/gingival tissues for long-term stability of dental implants.Materials and Methods: In this study, submicro-nano structures were created on PEEK surface by FSL with power of 80 mW (80FPK) and 160 mW (160FPK).Results: Compared with PEEK, both 80FPK and 160FPK with submicro-nano structures exhibited elevated surface performances (hydrophilicity, surface energy, roughness and protein absorption). Furthermore, in comparison with 80FPK, 160FPK further enhanced the surface performances. In addition, compared with PEEK, both 80FPK and 160FPK significantly excited not only the responses (adhesion, proliferation, alkaline phosphatase [ALP] activity and osteogenic gene expression) of MC3T3-E1 cells but also responses (adhesion as well as proliferation) of GE cells of human in vitro. Moreover, in comparison with 80FPK, 160FPK further enhanced the responses of MC3T3-E1 cells/GE cells.Conclusion: FSL created submicro-nano structures on PEEK with elevated surface performances, which played crucial roles in exciting the responses of MC3T3-E1 cells/GE cells. Consequently, 160FPK with elevated surface performances and outstanding cytocompatibility would have enormous potential as an implant for dental replacement.Keywords: polyetheretherketone; PEEK, surface modification, submicro-nano structures, functional group, cell responses

Polyetherketoneketone (PEKK) exhibits admirable biocompatibility and mechanical performances but bioinert while tantalum (Ta) possesses excellent osteogenesis and osseointegration but high elastic modulus and density, and processing is too difficult and expensive. In the present study, combining of the advantages of both PEKK and Ta, implantable composites of PEKK/Ta were fabricated by blending PEKK with Ta microparticles of 20 v% (PT20) and 40 v% (PT40) content. In comparison with PT20 and PEKK, the surface hydrophilicity, surface energy, roughness and proteins adsorption as well as mechanical performances of PT40 significantly increased because of the higher Ta particles content in PEKK. Furthermore, PT40 exhibited the mechanical performances (e.g., compressive strength and modulus of elasticity) close to the cortical bone of human. Compared with PT20 and PEKK, PT40 with higher Ta content remarkably enhanced the responses (including adhesion, proliferation and osteogenic differentiation) of MC3T3-E1 cells in vitro. Moreover, PT40 markedly improved bone formation as well as osseointegration in vivo. In short, incorporation of Ta microparticles into PEKK created implantable composites with improved surface performances, which played key roles in stimulating cell responses/bone formation as well as promoting osseointegration. PT40 might have great potential for bear-loading bone substitute., Graphical abstract Image 1, Highlights • Bioactive composites of PEKK/Ta (PT) were fabricated by melt blending. • Compressive strength, bending strength and elastic modulus significantly increased with Ta content increasing. • Hydrophilicity, surface energy, roughness and protein adsorption remarkably enhanced with Ta content increasing. • PT40 significantly promoted the responses (adhesion, proliferation and osteogenic differentiation) of MC3T3-E1 cells. • PT40 obviously accelerated osteogenesis and osseointegration in vivo.

Nanoporous tantalum pentoxide (NTP) particles with a pore size of about 10 nm were synthesized and blended with polyetheretherketone (PEEK) to fabricate a PEEK/NTP composite (PN). Subsequently, PN was treated by concentrated sulfuric acid to create a microporous surface (pore size of around 2 μm) on sulfonated PN (SPN), which formed a hierarchical micro & nanoporous surface. Compared with PN, the porous surface of SPN exhibited higher roughness, hydrophilicity, and surface energy. In addition, genistein (GT) was loaded into the porous surface of SPN (SPNG), which showed high GT loading capacity and sustained release of GT into phosphate buffered saline (PBS). Moreover, SPNG revealed excellent antibacterial activity, which inhibited bacterial (E. coli and S. aureus) growth in vitro due to the synergistic effects of both sulfonic acid (SO3H) groups and the sustained release of GT. Compared with PN, SPN significantly improved the adhesion, proliferation, and osteogenic differentiation of bone mesenchymal stem cells in vitro. Moreover, compared with SPN, SPNG further enhances the cell responses. Compared with PN, SPN remarkably improved bone formation and osteointegration in vivo. Furthermore, compared with SPN, SPNG further enhanced the osteointegration. In short, SPNG with a micro & nanoporous surface, SO3H groups, and the sustained release of GT exhibited antibacterial activity and accelerated osteointegration, which would have tremendous potential as drug-loaded implants for bone substitute.

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Departamento de Filología Española. Fecha de Lectura: 23-02-2022

To improve the bioperformances of porous polyetheretherketone (PPK) for bone repair, silicon nitride-coated PPK (CSNPPK) was prepared by a method of suspension coating and melt binding. The results revealed that, as compared with PPK, the surface roughness, compressive strength, and water absorption of CSNPPK increased, while the pore size and porosity of CSNPPK exhibited no obvious changes. In addition, the cellular responses (including attachment, proliferation, and differentiation as well as osteogenically related gene expressions) of the MC3T3-E1 cells to CSNPPK were remarkably promoted compared with PPK and dense polyetheretherketone in vitro. Moreover, in the model of rabbit femoral condyle defects, the results of micro computed tomography and histological and mechanical evaluation revealed that the ingrowth of new vessels and bone tissues into CSNPPK was significantly greater than that into PPK in vivo. Furthermore, the load-displacement and push-out loads for CSNPPK with bone tissues were higher than for PPK, indicating good osseointegration. In short, CSNPPK not only promoted vascularization but also enhanced osteogenesis as well as osseointegration in vivo. Therefore, it can be suggested that CSNPPK with good biocompatibility, osteogenic activity, and vascularization might be a promising candidate as an implant for bone substitute and repair.

Zhiying Pang,1,* Zhangyi Pan,1,* Min Ma,1 Zhiyan Xu,2 Shiqi Mei,2 Zengxin Jiang,3 Feng Yin1 1Department of Joint Surgery, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai 200092, People’s Republic of China; 2Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237, People’s Republic of China; 3Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Shanghai 200032, People’s Republic of China*These authors contributed equally to this workCorrespondence: Zengxin Jiang Tel +86 21-64041990Email Dr_Jiangzx@163.comFeng Yin Tel +86 21-64041990Email 001yinfeng@sina.comPurpose: As a dental material, polyetheretherketone (PEEK) is bioinert that does not induce cellular response and bone/gingival tissues regeneration. This study was to develop bioactive coating on PEEK and investigate the effects of coating on cellular response.Materials and Methods: Tantalum pentoxide (TP) coating was fabricated on PEEK surface by vacuum evaporation and responses of rat bone marrow mesenchymal stem (RBMS) cells/human gingival epithelial (HGE) were studied.Results: A dense coating (around 400 nm in thickness) of TP was closely combined with PEEK (PKTP). Moreover, the coating was non-crystalline TP, which contained many small humps (around 10 nm in size), exhibiting a nanostructured surface. In addition, the roughness, hydrophilicity, surface energy, and protein adsorption of PKTP were remarkably higher than that of PEEK. Furthermore, the responses (adhesion, proliferation, and osteogenic gene expression) of RBMS cells, and responses (adhesion and proliferation) of HGE cells to PKTP were remarkably improved in comparison with PEEK. It could be suggested that the nanostructured coating of TP on PEEK played crucial roles in inducing the responses of RBMS/HGE cells.Conclusion: PKTP with elevated surface performances and outstanding cytocompatibility might have enormous potential for dental implant application.Keywords: polyetheretherketone, tantalum pentoxide, nanostructured coating, cytocompatibility, dental implant applications

Poly(propylene carbonate) (PPC) has aroused extensive attention in the biomaterial field because of its excellent biocompatibility and appropriate degradability, but surface hydrophobicity and bioinertness limit its applications for bone repair and tissue engineering. In this study, a bioactive PPC/laponite (LAP) nanocomposite (PL) was prepared by a melt-blending method, and a microporous surface on PPC and PL (PT and PLT) was created by sodium hydroxide (NaOH) treatment. The results demonstrated that the surface roughness, hydrophilicity, surface energy, and degradability as well as protein adsorption of PLT were obviously improved compared with PPC. Moreover, the degradability of PLT was remarkably enhanced with a slight increase of pH values in Tris-HCl solution. Furthermore, adhesion and proliferation as well as osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs) to PLT were significantly promoted compared with PPC. The results suggested that incorporating LAP into PPC obviously improved the surface performance of PL (with nanotopography), and surface treatment with NaOH further enhanced surface properties of PLT (with micronanotopography and hydrophilic groups), which significantly promoted responses of rBMSCs. In short, PLT displayed excellent cytocompatibility, which would have great potential for bone regeneration.

A bioactive coating of nanoporous magnesium calcium silicate (n-MCS) on polyetheretherketone (ncPK) surface was prepared, and dual drugs of genistein (GS) and curcumin (CR) were co-loaded into coating of ncPK (dncPK). The results revealed that compared with polyetheretherketone (PEEK), surface roughness, wettability and apatite mineralization ability of both ncPK and dncPK obviously improved, which promoted the rat bone mesenchymal stem cells (rBMSCs) adhesion. In addition, compared with ncPK and PEEK, dncPK significantly promoted the proliferation and differentiation of rBMSCs. Compared with ncPK and PEEK, dncPK displayed superior antibacterial activity to Escherichia coli and Staphylococcus aureus. The Micro-CT, histological and push-out load evaluations revealed that compared with ncPK and PEEK, dncPK remarkably accelerated osteogenesis and osseointegration in vivo. The results demonstrated that dual drugs-loaded dncPK exhibited good antibacterial activity and osteogenic activity, and significantly enhanced osteogenesis and osseointegration, which could be an alternative candidate as an implant in orthopedic and dental applications. Keywords: Polyetheretherketone, Nanoporous coating, Dual drugs, Antibacterial activity, Osseointegration

Surface characteristics of the biomaterials have significant effects on response of osteoblast and formation of new bone tissue. In this study, to improve the bio-performance of polyimide (PI) as an implantable material for bone substitute, concentrated sulfuric acid suspension with tantalum (V) oxide (vTO) submicro-particles of 10w% (PIST10) and 15w% (PIST15) was utilized to modify PI surface. After sulfonation, microporous coatings including vTO particles were created on PI (PIST10 and PIST15) while microporous coating without vTO particles was also created on PI (PIS). Results showed that surface roughness, hydrophilicity and protein adsorption of PIST15 was remarkably higher than PIST10 and PIS. Furthermore, after soaking into simulated body fluid (SBF), no apatite mineralization on PIS was found, while PIST15 with high vTO content exhibited better apatite mineralization compared with PIST10. Moreover, PIS showed low antibacterial property, while PIST15 with high vTO content revealed better antibacterial property compared with PIST10. In addition, cellular response (such as adhesion, proliferation and alkaline phosphatase activity) of bone marrow stromal cells (BMSC) of rat to PIST15 was higher than PIST10 and PIS. In conclusion, the microporous coating of PIST15 including vTO submicro-particles possessed good antibacterial property and bioactivity, which significantly promoted the responses of BMSC. Therefore, PIST15 has potential application prospects for bone substitute.

To improve the surface bio-performances of polyimide (PI), tantalum pentoxide (Ta2O5)/PI composites (TPC) were prepared, and concentrated sulfuric acid was utilized to modify TPC surface. The results revealed that sulfonated TPC (STPC) exhibited microporous surface with pores size of about 3 μm, and sulfonic acid (-SO3H) groups were introduced onto the microporous surface. In addition, many Ta2O5 submicro particles appeared on the microporous surface, which formed micro-submicro structures. Compared with PI, the surface roughness, hydrophilicity, surface energy and protein adsorption as well as apatite mineralization of STPC in simulated body fluid were obviously enhanced, which increased with Ta2O5 content increasing. In addition, STPC exhibited antibacterial performances due to the presence of -SO3H groups and Ta2O5. Furthermore, the responses (adhesion, proliferation and differentiation) of rat bone marrow mesenchymal stem cells to STPC were remarkably promoted with the increase of Ta2O5 content. In short, STPC with 50w% Ta2O5 content (STPC 50) with sulfonated microporous surface contained micro-submicro structures, which exhibited antibacterial performances and stimulated cell responses. STPC50 with improved surface properties and cytocompatibility might have large potentials for bone repair applications. Keywords: Tantalum pentoxide, Polyimide based composite, Sulfonation, Micro-submicro structures, Antibacterial performances

Polyetheretherketone (PEEK) biomaterial has become increasingly popular in orthopedic applications due to its favorable biocompatibility, biostability, mechanical strength and elastic modulus similar to natural bones. In this research, in order to improve the biological performances of PEEK, tantalum pentoxide (Ta2O5) was incorporated into PEEK to fabricate PEEK/Ta2O5 composites (PTC) using a method of cold press-sintering, and surface coarsening of PTC was prepared by sand blasting. The results showed that the Ta2O5 particles were uniformly disperse into PEEK, and thermal and mechanical properties of PTC were enhanced with the increase of Ta2O5 content. In addition, incorporating Ta2O5 into PEEK and surface coarsening could improve surface roughness, hydrophilicity, surface energy and protein absorption of PTC. Furthermore, the adhesion and proliferation as well as osteogenic differentiation of BMSCs on PTC were significantly promoted and regulated by Ta2O5 content and surface coarsening. The results indicated that surface coarsening of PTC (PTCS) with high surface roughness, hydrophilicity and surface energy could induce positive cellular responses, showing good cytocompatibility. PTCS might have a great potential as implants for bone repair.

Polyimide (PI) may become a promising biomaterial for dental and orthopedic application due to its high mechanical strength, good biocompatibility and bio-stability as well as modulus of elasticity similar to the bone of human body. In this study, bioactive tantalum pentoxide (Ta2O5, TO)/polyimide (PI) composites (TPC) were fabricated by blending modification through a process of cold-pressing and sintering. The results revealed that the compressive strength, thermal stability, surface roughness, hydrophilicity and surface energy of TPC were significantly enhanced with the increase of TO content. Moreover, apatite mineralization of TPC in simulated body fluid (SBF) was obviously improved, in which TPC with TO of 50 wt% content (TPC50) displayed the best bioactivity. Furthermore, the cellular responses (adhesion, proliferation and differentiation) of rat bone mesenchymal stem cells (rBMSCs) to TPC were obviously upregulated with the increase of TO content. The results demonstrated that the TO content in the composites remarkably affected not only physical-chemical properties but also the cells behaviors. It can be suggested that TPC50 with improved surface properties and bioactivity as well as good cytocompatibility would have great potential and prospect for dental and orthopedic applications.