BACKGROUND:Steroid-induced femoral head necrosis is mostly caused by long-term and extensive use of hormones,but its specific pathogenesis is not yet clear and needs further study. OBJECTIVE:To screen out the differential miRNAs in osteoclast exosomes after the intervention of Panax notoginseng saponins,and on this basis,to further construct an osteogenic-related ferroptosis regulatory network to explore the potential mechanism and research direction of steroid-induced osteonecrosis of the femoral head. METHODS:MTT assay was used to detect the toxic effects of different concentrations of dexamethasone and different mass concentrations of Panax notoginseng saponins on Raw264.7 cell line.Tartrate resistant acid phosphatase staining and TUNEL assay were used to detect the effects of Panax notoginseng saponins on osteoclast inhibition and apoptosis.Exosomes were extracted from cultured osteoclasts with Panax notoginseng saponins intervention.Exosomes from different groups were sequenced to identify differentially expressed miRNAs.CytoScape 3.9.1 was used to construct and visualize the regulatory network between differentially expressed miRNAs and mRNAs.Candidate mRNAs were screened by GO analysis and KEGG analysis.Finally,the differential genes related to ferroptosis were screened out,and the regulatory network of ferroptosis-related genes was constructed. RESULTS AND CONCLUSION:(1)The concentration of dexamethasone(0.1 μmol/L)and Panax notoginseng saponins(1 736.85 μg/mL)suitable for intervention of Raw264.7 cells was determined by MTT assay.(2)Panax notoginseng saponins had an inhibitory effect on osteoclasts and could promote their apoptosis.(3)Totally 20 differentially expressed miRNAs were identified from osteoclast-derived exosome samples,and 11 differentially expressed miRNAs related to osteogenesis were predicted by target mRNAs.The regulatory networks of 4 up-regulated differentially expressed miRNAs corresponding to 155 down-regulated candidate mRNAs and 7 down-regulated differentially expressed miRNAs corresponding to 238 up-regulated candidate mRNAs were constructed.(4)Twenty-four genes related to ferroptosis were screened out from the differential genes.Finally,12 networks were constructed(miR-98-5p/PTGS2,miR-23b-3p/PTGS2,miR-425-5p/TFRC,miR-133a-3p/TFRC,miR-185-5p/TFRC,miR-23b-3p/NFE2L2,miR-23b-3p/LAMP2,miR-98-5p/LAMP2,miR-182-5p/LAMP2,miR-182-5p/TLR4,miR-23b-3p/ZFP36,and miR-182-5p/ZFP36).These results indicate that Panax notoginseng saponins may regulate osteoblast ferroptosis by regulating the expression of miRNAs derived from osteoclast exosomes,thus providing a new idea for the study of the mechanism of steroid-induced femoral head necrosis.

With the widespread use of antibiotics, drug-resistant bacterial infections have become a significant threat to human health. Finding new antibacterial strategies that can effectively control drug-resistant bacterial infections has become an urgent task. Unlike small molecule drugs that target bacterial proteins, antisense oligonucleotide (ASO) can target genes related to bacterial resistance, pathogenesis, growth, reproduction and biofilm formation. By regulating the expression of these genes, ASO can inhibit or kill bacteria, providing a novel approach for the development of antibacterial drugs. To overcome the challenge of delivering antisense oligonucleotide into bacterial cells, various drug delivery systems have been applied in this field, including cell-penetrating peptides, lipid nanoparticles and inorganic nanoparticles, which have injected new momentum into the development of antisense oligonucleotide in the antibacterial realm. This review summarizes the current development of small nucleic acid drugs, the antibacterial mechanisms, targets, sequences and delivery vectors of antisense oligonucleotide, providing a reference for the research and development of antisense oligonucleotide in the treatment of bacterial infections.

This study investigated the effect of different carrier materials on the in vitro properties of progesterone solid dispersions. The solid dispersions of the insoluble drug progesterone were prepared by hot melt extrusion technique using rheological properties as the index of investigation, and the in vitro properties of the solid dispersions were characterized. Scanning electron microscope revealed solid dispersions with rough surfaces and agglomerated microstructures into irregular lumpy particles. Differential scanning calorimetry and powder X-ray diffraction showed the change of progesterone crystalline form in solid dispersions from crystalline to amorphous state. In vitro dissolution studies showed that solid dispersions prepared with different carrier materials can effectively improve the dissolution rate of drugs. The results of the study showed that the type of carrier material had a significant effect on the in vitro properties of solid dispersions, providing a reference for the study of solid dispersions in the controlled release of insoluble drugs.

Needle-free injection technology (NFIT) refers to the drug delivery systems in which drugs are propelled as high-speed jet streams using any of the pressure source to penetrate the skin to the required depth. NFIT is a promising drug delivery system as it enables the injection of liquids, powders, and depot/projectiles, and has the advantages of preventing needle stick accidents, improving drug bioavailability, eliminating needle-phobia, increasing vaccine immunity, simplifying operations and is convenient for patients to use. NFIT and its research background, the structure and classification of needle-free jet injectors (NFJI), drugs that can be delivered using NFJI and the factors affecting the injection effect are comprehensively reviewed in this paper. The limitations and potential development directions are summarized to provide a theoretical basis for the application and development of NFIT.

Umbilical cord mesenchymal stem cells (UC-MSCs) have been widely used in regenerative medicine, but there is limited research on the stability of UC-MSCs formulation during production. This study aims to assess the stability of the cell stock solution and intermediate product throughout the production process, as well as the final product following reconstitution, in order to offer guidance for the manufacturing process and serve as a reference for formulation reconstitution methods. Three batches of cell formulation were produced and stored under low temperature (2-8 ℃) and room temperature (20-26 ℃) during cell stock solution and intermediate product stages. The storage time intervals for cell stock solution were 0, 2, 4, and 6 h, while for intermediate products, the intervals were 0, 1, 2, and 3 h. The evaluation items included visual inspection, viable cell concentration, cell viability, cell surface markers, lymphocyte proliferation inhibition rate, and sterility. Additionally, dilution and culture stability studies were performed after reconstitution of the cell product. The reconstitution diluents included 0.9% sodium chloride injection, 0.9% sodium chloride injection + 1% human serum albumin, and 0.9% sodium chloride injection + 2% human serum albumin, with dilution ratios of 10-fold and 40-fold. The storage time intervals after dilution were 0, 1, 2, 3, and 4 h. The reconstitution culture media included DMEM medium, DMEM + 2% platelet lysate, 0.9% sodium chloride injection, and 0.9% sodium chloride injection + 1% human serum albumin, and the culture duration was 24 h. The evaluation items were viable cell concentration and cell viability. The results showed that the cell stock solution remained stable for up to 6 h under both low temperature (2-8 ℃) and room temperature (20-26 ℃) conditions, while the intermediate product remained stable for up to 3 h under the same conditions. After formulation reconstitution, using sodium chloride injection diluted with 1% or 2% human serum albumin maintained a viability of over 80% within 4 h. It was observed that different dilution factors had an impact on cell viability. After formulation reconstitution, cultivation in medium with 2% platelet lysate resulted in a cell viability of over 80% after 24 h. In conclusion, the stability of cell stock solution within 6 h and intermediate product within 3 h meets the requirements. The addition of 1% or 2% human serum albumin in the reconstitution diluent can better protect the post-reconstitution cell viability.

Osteonecrosis of the femoral head(ONFH)is a common and intractable disease in orthopedics,and its occurrence is associated with lipid metabolism disorders,endothelial dysfunction,bone homeostasis imbalance,genetic polymorphism,etc.However,the specific mechanism has not been fully elucidated.ONFH has an insidious progression in the early stages,and in the later stages,it often requires hip replacement surgery,which imposes a heavy economic burden on patients and society.Non-coding RNA has been the hotspot of medical research in recent years,and increasing number of non-coding RNA has been found to regulate the occurrence and development of ONFH through various mechanisms.This article reviews the research progress on the role of non-coding RNA in the occurence,development and treatment of ONFH,in order to provide reference for the treatment of ONFH.

Objective:To explore the effects of the scaffolding-based flipped classroom approach in the teaching of Infectious Disease Nursing. Methods:We assigned 152 students of nursing and midwifery majors of grade 2018 (experimental group) to be taught using the scaffolding-based flipped classroom approach and 182 students of grade 2017 (control group) to be taught using the traditional lecture method. Teaching effects were evaluated through students' exam performance and a questionnaire survey. Numerical data were analyzed using the χ2 test and t test with the use of SPSS 18.0, and text data were processed using NVivo 11 for thematic analysis. Results:The experimental group and control group showed significant differences in the interim exam score (83.19±7.96 vs. 79.62±3.14, P<0.001) and final exam score (78.47±6.92 vs. 73.16±8.24, P<0.001). The students of grade 2018 had a high level of participation in online learning. The questionnaire results showed that the scaffolding-based flipped classroom was well recognized in terms of students' overall perception, perceived course quality, perceived value of learning, and satisfaction and the open-ended question, with low scores for learner complaints and loyalty. Conclusions:The scaffolding-based flipped classroom is feasible in the teaching of Infectious Disease Nursing, which can improve students' academic performance and overall competence.