Concerns of Technical Evaluation on Registration of All-inside Meniscus Suture System / 中国医疗器械杂志

OBJECTIVE@#To summarize the product registration declaration ideas and registration technical review of the all-inside meniscal suture system, and to systematically think about of the technical review concerns of the all-inside meniscal suture system products to provide technical guidance for improving the quality of registration and application and regulatory efficiency.@*METHODS@#Consult the public information of such products at home and abroad, and summarize the experience of registration review of such products.@*RESULTS@#The technical review of the all-inside meniscus suture system registration mainly focuses on product basic information, pre-clinical research, clinical evaluation and product technical requirements.@*CONCLUSIONS@#The difficulty of product registration and declaration of the all-inside meniscus suture system lies in the provision of pre-clinical research data of the product, and the applicant needs to strengthen the basic research ability, formulate scientific technical indicators and test methods to ensure the safety and effectiveness of the product, and also provide sufficient supporting data for the registration declaration.

Discussion of Application Status and Key Attentions on Registration for Ossicular Replacement Prosthesis / 中国医疗器械杂志

The ossicular replacement prosthesis should have good biocompatibility, stability, easy to install, and excellent sound transmission capacity. In this study, the characteristics of ideal materials for the ossicular replacement prosthesis were analyzed by searching the types of materials used in clinical practice and comparing the advantages and disadvantages of various materials and structures. At the same time, in combination with the current evaluation requirements and evaluation experience, the focus of the performance research project of ossicular replacement prosthesis in the process of registration is discussed to clarify the performance evaluation requirements of these products, so as to provide reference for the future work of manufacturers and regulators. The performance evaluation of ossicular replacement prosthesis focuses on its mechanical properties, fixation stability, sound transmission characteristics, biological characteristics, and magnetic resonance compatibility.

Discussion and Concern on Animal Study for Orthopaedic Implantable Devices / 中国医疗器械杂志

In recent years, new orthopaedic implantable devices continue to emerge, which require higher requirements for technical evaluation. Animal study is an important part of the research and development process for the new orthopedic implantable devices, which provides relevant evidence for product design and stereotyping. By introducing the purpose of animal study, and the application of 3R principle (replacement, reduction, refinement) in this field, we summarize the concern on the animal study, in order to provide reference for the development and research of new orthopedic implantable devices and biomaterials. At the same time, the application of evidence-based research methods such as systematic review in the field is introduced, which provides new tools and approaches for the technical review and regulatory science.

Functionalization of biomedical materials using fusion peptides for tissue regeneration.

Tissue development deformity or tissue defect is a major clinical challenge. Tissue engineering technology provides a promising solution to these problems. Among them, functional biomaterials with regenerative abilities are one of the development trends. Polypeptide is a small molecule that can be used to modify tissue engineering materials. However, the function of a single polypeptide molecule is limited and insufficient to construct comprehensive microenvironment for tissue regeneration. Fusion peptides combining two or more polypeptide molecules with different functions were expected to achieve multiple efficaciesin vivo, providing a novel solution for clinical tissue regeneration engineering applications. This paper reviews the construction methods, degradation process, and biological activities of fusion peptides, and presents recent global research progress and prospects concerning fusion peptides. It provides a reference helping to guide the future exploration and development of fusion peptide-based functional biomaterials for tissue engineering.

Immune responses elicited by influenza A mRNA vaccine based on lipopolyplex-encapsulated virus nucleoprotein and matrix protein 2 extracellular domain fusion in mice / 中华微生物学和免疫学杂志

Objective:To evaluate the immunogenicity of a novel influenza virus mRNA vaccine based on conserved antigens delivered by lipopolyplex (LPP) platform in a mouse model.Methods:Four copies of genes coding for extracellular domain of matrix 2 protein (M2e) and nucleoprotein (NP) of influenza A virus were synthetized after codon optimization. The fusion antigens were transcribed in vitro and delivered by LPP platform, named as LPP-4M2eNP. Expression of M2e and NP in eukaryotic cells was detected by immunofluorescence assay (IFA). BALB/c mice were inoculated intramuscularly twice with 10 μg or 30 μg LPP-4M2eNP vaccine at an interval of four weeks. Antibody response was detected by ELISA and cellular-mediated immunity (CMI) was detected by enzyme-linked immunospot assay (ELISPOT). Results:IFA showed that NP and M2e were expressed correctly in eukaryotic cells. Single dose immunization could induce significant antigen (NP, M2e)-specific CMI and antigen (NP, M2e)-specific antibody response was induced in mice with Th1 type bias after boost immunization. Moreover, NP-specific CMI was increased significantly after the second immunization, while no significant change in M2e-specific CMI was observed.Conclusions:Stronger CMI was triggered in mice by single dose of LPP-4M2eNP vaccine. Furthermore, robust humoral and cellular immune responses were induced after boost immunization. This study suggested that LPP-4M2eNP vaccine, which based on conserved antigen of influenza A and delivered by LPP platform, had great potential for development and application.

A tandem-repeat dimeric RBD protein-based COVID-19 vaccine ZF2001 protects mice and nonhuman primates

A safe, efficacious and deployable vaccine is urgently needed to control COVID-19 pandemic. We report here the preclinical development of a COVID-19 vaccine candidate, ZF2001, which contains tandem-repeat dimeric receptor-binding domain (RBD) protein with alum-based adjuvant. We assessed vaccine immunogenicity and efficacy in both mice and non-human primates (NHPs). ZF2001 induced high levels of RBD-binding and SARS-CoV-2 neutralizing antibody in both mice and NHPs, and also elicited balanced TH1/TH2 cellular responses in NHPs. Two doses of ZF2001 protected Ad-hACE2-transduced mice against SARS-CoV-2 infection, as detected by reduced viral RNA and relieved lung injuries. In NHPs, vaccination of either 25 g or 50 g ZF2001 prevented infection with SARS-CoV-2 in lung, trachea and bronchi, with milder lung lesions. No evidence of disease enhancement is observed in both models. ZF2001 is being evaluated in the ongoing international multi-center Phase 3 trials (NCT04646590) and has been approved for emergency use in Uzbekistan.

Analysis of Key Points and Difficulties in Registration Application of Inflatable Bone Expander / 中国医疗器械杂志

With the advantages of inflatable bone expander in the treatment of osteoporotic vertebral compression fractures, the number of applications for registration of such products is increasing. Based on the characteristics of the medical device, this article analyzed and summarized the relevant requirements for the basic information, product performance research, product manufacturing, clinical evaluation, and product instructions that should be focused on the registration application dossiers, as well as comply with the requirements of CMDE. The focus of the registration application for Inflatable Bone Expander should be the standardization of the application dossiers, while the difficulty was the scientific rationality of the research data. Comments and suggestions are provided to relevant practitioners on standardization of registration application dossiers. It may help them to optimize the quality of registration application dossiers while improve the efficiency of registration applications.

Design, synthesis and biological evaluation of 2-indolinone derivatives as PAK1 inhibitors in MDA-MB-231 cells.

P21-activated kinase 1 (PAK1) plays a vital role in the proliferation, survival and migration of cancer cells, which has emerged as a promising drug target for cancer therapy. In this study, a series of 2-indolinone derivatives were designed and synthesized through a structure-based strategy. A potent PAK1 inhibitor (ZMF-005) was discovered, which presented an IC50 value of 0.22 µM against PAK1 with potent antiproliferative activity. Furthermore, we predicted the binding mode of ZMF-005 and PAK1 by molecule docking and dynamic (MD) simulation. In addition, ZMF-005 was documented to induce significant apoptosis and suppress migration in MDA-MB-231 cells. Collectively, these findings revealed that ZMF-005 is a novel potent PAK1 inhibitor for breast cancer treatment.

Research advances in nonalcoholic fatty liver disease in lean individuals / 临床肝胆病杂志

The incidence rate of nonalcoholic fatty liver disease (NAFLD) is continuously increasing in the world, and NAFLD is a major cause of chronic liver disease in developed countries such as the United States and may become the most common chronic liver disease in China in the future. NAFLD is often observed in the obese population; however, it is also commonly seen in lean individuals. This article summarizes the latest studies on lean NAFLD and elaborates on the following pathogeneses of this disease: the change in single nucleotide polymorphism is one of the predisposing factors for NAFLD in the lean population; the change of gut microbiota and sarcopenia may induce a variety of metabolic disorders including hyperlipidemia, hyperuricemia, insulin resistance, and iron metabolic disorders, and such metabolic disorders may promote the development of NAFLD; in addition, unhealthy dietary habits and lifestyle may contribute to the accumulation of fat and increase the burden of the liver. The combined effect of these factors eventually lead to the development of NAFLD, but further studies are still needed to clarify the pathogenesis of lean NAFLD.

Levamisole promotes murine bone marrow derived dendritic cell activation and drives Th1 immune response in vitro and in vivo.

Our lab previously found that levamisole (LMS) as an adjuvant enhanced the efficacy of vaccine against infectious pathogens. However, the cellular and molecular mechanisms remain to be defined. In this study, we showed that BALB/c bone marrow-derived DC stimulated with LMS resulted in enhanced cell-surface expression of CD80, CD86, CD40 and MHC class II, as well as enhanced production of IL-12p70, TNF-α and IL-1ß. Interestingly, the LMS activated DCs were able to stimulate CD4(+) T cell proliferation and facilitated Th1 differentiation by increasing the secretion of IFN-γ in an allogeneic mixed leukocyte reaction. Furthermore, to confirm the in vitro data, we investigated the effect of LMS on antigen-specific antibody and cytokine production in BALB/c mice. Immunization with LMS plus OVA showed that anti-OVA IgG2a and IFN-γ were increased significantly compared with OVA alone in BALB/c mice. In conclusion, our results suggested that murine bone marrow-derived DC, played a crucial role in the effect of LMS on the induction of Th1 responses, which probably was due to its ability to promote DC maturation and secrete proinflammatory cytokines.

Deep sequencing-based analysis of gene expression in bovine mammary epithelial cells after Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae infection.

The goal of this study was to characterize the transcriptome of primary bovine mammalian epithelial cells (pBMECs) and to identify candidate genes for response and resistance to Staphylococcus aureus (strain S108), Escherichia coli (strain E23), and Klebsiella pneumoniae (strain K96) infection. Using Solexa sequencing, approximately 4.9 million total sequence tags were obtained from each of the three infected libraries and the control library. Gene Ontology (GO) analysis of the S108-infected pBMECs showed differentially expressed genes (DEGs) were significantly involved in metabolic processes. In E23-infected pBMECs, DEGs were predominantly associated with cell death and programmed cell death GO terms, while in K96-infected pBMECs, DEGs were primarily involved in metabolic processes and in utero embryonic development. Analysis of the cluster of orthologous groups of proteins showed that the S108-infected, E23-infected and K96-infected pBMECs were significantly involved in "Translation, ribosomal structure and biogenesis", "General function prediction only" and "Replication, recombination and repair". The transcriptome sequences were also annotated for KEGG orthology, and it was found that DEGs in S108-infected pBMECs were significantly involved in oxidative phosphorylation and Parkinson's disease. The clustered pathway terms of the DEGs of the E23-infected pBMECs were found to involve the NOD-like receptor signaling pathway and oxidative phosphorylation, while those of the K96-infected pBMECs were primarily involved in oxidative phosphorylation and apoptosis. Our results have identified a number of immune-related genes that showed changes in gene expression after bacterial infection, and provided insight into the interactions between pBMECs and the bacteria.