Objective To investigate the memory amelioration of the Alzheimer disease (AD)model rat after being transplanted the single neural stem cells(NSC) and NSC modified with human brain-derived neurotrophic factor（hBDNF） gene. Methods Forty SD rats were divided evenly into 4 groups randomly. The AD model rats were made by cutting unilaterallythe fibria fornix of male rats. Ten to twelve days after surgery, the genetically modified and unmodified NSC were implanted into the lateral cerebral ventricle of group Ⅲ and group Ⅳ respectively. Two weeks after transplantation, theamelioration of memory impairment of the rats was detected by Morris water maze. Results The average escaping latency of the group Ⅲ and group Ⅳ (41.84±21.76 s,25.23±17.06 s respectively) was shorter than that of the group Ⅱ(70.91±23.67 s) (Plt;0.01). The percentage of swimming distance inthe platform quadrant in group Ⅲ (36.9%) and in group Ⅳ(42.0%) was higherthan that in the group Ⅱ(26.0%) (Plt;0.01). More marginal and random strategies were used in group Ⅱ.The percentage of swimming distance in the platform quadrant in group Ⅳ was also greater than that in group Ⅲ(Plt;0.05). There were no significant differences in the average escaping latency, the percentage of swimming distance in the platform quadrant and the probe strategy between group Ⅳ and group Ⅰ(Pgt;0.05).More lineal and oriented strategies were used in group Ⅳ. Conclusion The behavioral amelioration of AD model rat was obtained by transplanting single NSC and hBDNF-gene-modified NSC. The effect of the NSC group modified with hBDNF gene is better than that of the groupⅢ.
Time-to-event outcomes are a key component in survival analyses. Effect modification by time, also known as interaction between effect and time, can exist in time-to-event data and influence the analysis process. Our objective is to discuss the proper methods to conduct evidence synthesis of time-to-event data when effect modification by time exists.
ObjectiveTo analyze effects of histone demethylase Jumonji-domaincontaining protein 3 (JMJD3) in macrophages in order to provide a new target for treatment of macrophage-related inflammatory reactions, autoimmune diseases, and organ transplantation rejection.MethodThe related literatures of researches on the effects of JMJD3 in the macrophages in recent years were searched and reviewed.ResultsThe macrophages played the important roles in maintaining tissue homeostasis and host response, clearing pathogens and apoptotic cells, and promoting tissue repair and wound healing. The JMJD3 could regulate the balance of M1 and M2 types of macrophages through the different ways and had different effects on the polarization of M2 macrophages when it was stimulated by the different extracellular substances. In some immune diseases and wound repairing, the JMJD3 could not only promote the inflammatory responses, but also polarize the M2 macrophages so as to inhibit the inflammation and promote the tissue repair. Clinically, the JMJD3 expression might be different in the different diseases and its low or high expression both might be involved in the occurrence of diseases.ConclusionHistone demethylase enzyme JMJD3 is involved in macrophage polarization and expression of inflammatory genes, but there are still many problems that require further to be investigated.
ObjectiveTo review antibacterial/osteogenesis dual-functional surface modification strategy of titanium-based implants, so as to provide reference for subsequent research. MethodsThe related research literature on antibacterial/osteogenesis dual-functional surface modification strategy of titanium-based implants in recent years was reviewed, and the research progress was summarized based on different kinds of antibacterial substances and osteogenic active substances. ResultsAt present, the antibacterial/osteogenesis dual-functional surface modification strategy of titanium-based implants includes: ① Combined coating strategy of antibiotics and osteogenic active substances. It is characterized in that antibiotics can be directly released around titanium-based implants, which can improve the bioavailability of drugs and reduce systemic toxicity. ② Combined coating strategy of antimicrobial peptides and osteogenic active substances. The antibacterial peptides have a wide antibacterial spectrum, and bacteria are not easy to produce drug resistance to them. ③ Combined coating strategy of inorganic antibacterial agent and osteogenic active substances. Metal ions or metal nanoparticles antibacterial agents have broad-spectrum antibacterial properties and various antibacterial mechanisms, but their high-dose application usually has cytotoxicity, so they are often combined with substances that osteogenic activity to reduce or eliminate cytotoxicity. In addition, inorganic coatings such as silicon nitride, calcium silicate, and graphene also have good antibacterial and osteogenic properties. ④ Combined coating strategy of metal organic frameworks/osteogenic active substances. The high specific surface area and porosity of metal organic frameworks can effectively package and transport antibacterial substances and bioactive molecules. ⑤ Combined coating strategy of organic substances/osteogenic active substancecs. Quaternary ammonium compounds, polyethylene glycol, N-haloamine, and other organic compounds have good antibacterial properties, and are often combined with hydroxyapatite and other substances that osteogenic activity. ConclusionThe factors that affect the antibacterial and osteogenesis properties of titanium-based implants mainly include the structure and types of antibacterial substances, the structure and types of osteogenesis substances, and the coating process. At present, there is a lack of clinical verification of various strategies for antibacterial/osteogenesis dual-functional surface modification of titanium-based implants. The optimal combination, ratio, dose-effect mechanism, and corresponding coating preparation process of antibacterial substances and bone-active substances are needed to be constantly studied and improved.
Cardiovascular disease is one of the most common causes of death. Coronary artery stent implantation has been the most important method to cure coronary disease and inhibit angiostegnosis. However, restenosis and thrombus at the site of implanting cardiovascular devices remains a significant problem in the practice of interventional cardiology. Recently, lots of studies have revealed that endothelial impairment is considered as one of the most important mechanisms contributing to restenosis. As a result, the method of accelerating endothelial regeneration at the injury site could prevent restenosis and thrombus. Considering the surface modification of cardiovascular stent implantation, this paper summarizes the progress on this direction, especially for the prevention of cardiovascular restenosis. Furthermore, this paper also proposes the methods and the future developing prospects for accelerating in vivo re-endothelialization at the site of intravascular stent with different biological molecules.
The surface morphology of titanium metal is an important factor affecting its hydrophilicity and biocompatibility, and exploring the surface treatment strategy of titanium metal is an important way to improve its biocompatibility. In this study, titanium (TA4) was firstly treated by large particle sand blasting and acid etching (SLA) technology, and then the obtained SLA-TA4 was treated by single surface treatments such as alkali-heat, ultraviolet light and plasma bombardment. According to the experimental results, alkali-heat treatment is the best treatment method to improve and maintain surface hydrophilicity of titanium. Then, the nanowire network morphology of titanium surface and its biological property, formed by further surface treatments on the basis of alkali-heat treatment, were investigated. Through the cell adhesion experiment of mouse embryonic osteoblast cells (MC3T3-E1), the ability of titanium material to support cell adhesion and cell spreading was investigated after different surface treatments. The mechanism of biological activity difference of titanium surface formed by different surface treatments was investigated according to the contact angle, pit depth and roughness of the titanium sheet surface. The results showed that the SLA-TA4 titanium sheet after a treatment of alkali heat for 10 h and ultraviolet irradiation for 1 h has the best biological activity and stability. From the perspective of improving surface bioactivity of medical devices, this study has important reference value for relevant researches on surface treatment of titanium implantable medical devices.
RNA can be labeled by more than 170 chemical modifications after transcription, and these chemical modifications are collectively referred to as RNA modifications. It opened a new chapter of epigenetic research and became a major research hotspot in recent years. RNA modification regulates the expression of genes from the transcriptome level by regulating the fate of RNA, thus participating in many biological processes and disease occurrence and development. With the deepening of research, the diversity and complexity of RNA modification, as well as its physiological significance and potential as a therapeutic target, can not be ignored.
Retinoblastoma (RB) is a common intraocular tumor in children, often leading to blindness or disability, and its pathogenesis involves genetic and epigenetic regulation. Epigenetics regulates gene expression through mechanisms such as DNA methylation and histone modification without altering the DNA sequence, and the imbalance of its homeostasis is considered a crucial factor in the development and progression of RB. Therapeutic strategies targeting these abnormal modifications offer new potential treatment avenues for RB. Although current research has highlighted the importance of epigenetics in RB, the specific mechanisms of action, the relationship with genetic bases, and the development of targeted drugs remain largely unknown. Therefore, further in-depth research into the epigenetic mechanisms of RB is of great significance for elucidating its carcinogenic mechanisms, identifying effective therapeutic targets, and developing new drugs.
Objective To review the current researches of scaffold materials for skeletal muscle tissue engineering, to predict the development trend of scaffold materials in skeletal muscle tissue engineering in future. Methods The related l iterature on skeletal muscle tissue engineering, involving categories and properties of scaffold materials, preparative techniqueand biocompatibil ity, was summarized and analyzed. Results Various scaffold materials were used in skeletal muscle tissue engineering, including inorganic biomaterials, biodegradable polymers, natural biomaterial, and biomedical composites. According to different needs of the research, various scaffolds were prepared due to different biomaterials, preparative techniques, and surface modifications. Conclusion The development trend and perspective of skeletal muscle tissue engineering are the use of composite materials, and the preparation of composite scaffolds and surface modification according to the specific functions of scaffolds.
Objective To review the basical research progress of porous tantalum in bone tissue engineering. Methods The related basical research in fabrication, cytobiology, and surface modification of porous tantalum was reviewed and analyzed. Results The outstanding physiochemical properties of porous tantalum granted its excellent performance in biocompatibility and osteointegration, as well as promoting cartilage and tendon tissue restoration. However, the clinical utilization of porous tantalum is somehow greatly limited by the complex and rigid commercial fabrication methods and extraordinary high cost. Along with the publication of novel fabrication and surface modification technology, the application of porous tantalum will be more extensive, the promotion in bone tissue regeneration will be more prominent. Conclusion Porous tantalum has advantage in bone defect restoration, and significant breakthrough technology is needed in fabrication methods and surface modification.