1.Printing Process Quality Control of Bioprinting Medical Devices
Neng XIE ; Qixin CAO ; Jinwu WANG ; Yuanjing XU ; Changru ZHANG ; Ya WANG ; Zitong WANG
Chinese Journal of Medical Instrumentation 2024;48(3):245-250
Objective This study analyzes the risk points in the quality control of bioink and the main processes of bioprinting,clarifies and explores the quality control and supervision model for bioprinting medical devices,and provides theoretical and practical guidance to ensure the safety and effectiveness of bioprinting medical devices.Methods The quality control risk points throughout the bioprinting process were comprehensively analyzed,with a particular focus on bioprinting materials and key processes.The regulatory model and methods for bioprinting medical devices were examined.This research concentrated on critical technologies such as extrusion,laser-assisted,and in situ bioprinting,assessing their potential for clinical applications and regulatory challenges.Results Bioink from different sources should meet regulatory requirements.It is essential to ensure aseptic handling of raw materials and to validate sterilization under"worst-case"conditions.Conclusion As bioprinting technology advances rapidly,corresponding research into materials,processes,and quality risk control should be conducted to ensure the concurrent development of the regulatory system.This will continuously contribute to the orderly progression of the entire industry and human health.
2.Oxidized lipoprotein(a)induces endothelial cell pyroptosis by inhibiting the expres-sion of cytochrome b
Zitong CAO ; Yanjun CHEN ; Shiming TAN ; Yuzhu RAO ; Jingjing WANG ; Zeming CAI ; Zuo WANG
Chinese Journal of Arteriosclerosis 2024;32(7):558-566
Aim To explore the mechanism of oxidized lipoprotein(a)(oxLp(a))inducing pyroptosis of vascu-lar endothelial cells.Methods After incubating human umbilical vein endothelial cells(HUVEC)with 100 mg/L ox-Lp(a)for 24 hours,Western blot and RT-qPCR was used to detect pyroptosis related proteins,pro-inflammatory cytokines,mitochondrial related proteins NRF1,NRF2,PGC-1α and mitochondrial gene cytochrome b(CYTB),ELISA was used to detect the levels of inflammatory factors,scanning electron microscopy was used to detect cell membrane rup-ture,transmission electron microscopy was used to detect mitochondrial morphology,Hoechst33342/PI staining was used to detect cell apoptosis,MitoSOX probe was used to detect mitochondrial reactive oxygen species(mtROS),Flu-4AM probe was used to detect calcium ions,JC-1 probe was used to detect mitochondrial membrane potential(MMP),and Calcein AM staining was used to detect mitochondrial permeability transition pore(mPTP).Transfecting HUVEC with CYTB overexpressing lentivirus and analyzing its effects on oxLp(a)induced pyroptosis and mitochondrial function.Results After treatment with oxLp(a),the expression of NLRP3,pro-Caspase-1,Caspase-1,GSDMD and GSDMD-N proteins re-lated to pyroptosis were significantly increased(P<0.05);the protein and mRNA levels of CYTB and pro-inflammatory cy-tokine IL-1β,IL-18 were significantly increased(P<0.05).Small pores appeared on the cell membrane,the percentage of PI stained positive cells significantly increased(P<0.05).OxLp(a)significantly inhibited the expression of mito-chondrial related proteins NRF1,NRF2 and PGC-1α,and the expression of mitochondrial gene CYTB,promoted an in-crease in mtROS generation,Ca2+overload,a decrease in ATP levels,a decrease in MMP,an increase in mPTP values,and abnormal mitochondrial morphology.After transfection with pHelper 2.0 lentivirus vector overexpressing CYTB,it was found that oxLp(a)induced HUVEC pyroptosis and mitochondrial morphological and functional abnormalities were par-tially reversed by overexpression of CYTB.Conclusion oxLp(a)promotes mitochondrial morphological and functional abnormalities and induces HUVEC pyroptosis by downregulating CYTB.