Objective To observe the changes in intradiscal internal internal pressure before and after percutaneous nucleoplasty (PN) in the patients with discogenic low back pain (DLBP),and to explore the mechanism of PN for alleviating DLBP.Methods Thirty patients definitely diagnosed as DLBP undergoing PN in the orthopedic department of this hospital from June 2023 to October 2023 were selected.The internal pressure of the lumbar disc was measured before and after the surgery.The visual analog scale (VAS),Japa-nese orthopedic association score (JOA) and Oswestry disability index (ODI) were used to assess the pain level of the patients before operation and at postoperative 1 d,1 month,3 months.The surgical efficacy was e-valuated by using the modified MacNab criteria.The linear correlation analysis was used to observe the relation-ship between the internal pressure of lumbar disc and changes in each pain score,and the factors possibly affecting postoperative effect was analyzed by using the multivariate logistic regression analysis.Results Compared with be-fore the surgery,the immediate postoperative internal pressure of lumbar disc in the patients was significantly decreased.The JOA scores at postoperative 1 d,1 month and 3 months were significantly increased,while the VAS and ODI scores were significantly decreased,and the differences were statistically significant (P<0.05). The excellent rates of surgical efficacy at postoperative 1 d,1 month and 3 months were 66.7％,73.3％ and 63.3％,respectively.The internal pressure of lumbar disc difference value between before operation and on postoperative 1 d and internal pressure of lumbar disc decrease rate had no significant correlation with the change value of each pain score (P>0.05).The multivariate logistic regression analysis showed that the dis-ease duration and the decrease rate of internal pressure of lumbar disc were the influencing factors of clinical efficacy in PN (P<0.05).Conclusion The occurrence of DLBP may be related with the increase of internal pressure of lumbar disc.PN could effectively reduce internal pressure of lumbar disc and achieve the goal of pain relief.

OBJECTIVE To prepare C-phycocyanin nanoparticles （CPC-NPs） and evaluate the in vitro mechanism of CPC- NPs on acute lung injury induced by lipopolysaccharide （LPS） combined with seawater. METHODS Ion crosslinking method was used to prepare CPC-NPs using CPC as the drug， carboxymethyl chitosan （CMCS） as the carrier， and CaCl2 as the crosslinking agent. The basic characterization of CPC-NPs was carried out. Mouse alveolar type Ⅱ epithelial cells MLE-12 and macrophages RAW264.7 were divided into 7 groups： normal group （Con group）， model group （Mod group）， blank NPs group， CPC-NPs 30， 60， 120 and 240 μg/mL groups. Except for the Con group， all other groups were treated with a combination of 10 μg/mL LPS and 25% seawater for 6 hours. After modeling， each treatment group was treated with corresponding drugs for 24 hours. The levels of malondialdehyde （MDA）， total antioxidant capacity （T-AOC）， superoxide dismutase （SOD）， catalase （CAT）， and glutathione peroxidase （GSH-Px） in MLE-12 cells， as well as the expression levels of B-cell lymphoma-2 （Bcl-2）， Bcl-2 associated X protein （Bax）， caspase-3 protein and mRNA， CAT and glutathione S-transferase （GST） mRNA were determined. The levels of interleukin- 1β （IL-1β）， tumor necrosis factor-α （TNF-α） and IL-6 in RAW264.7 cells， as well as the expression levels of NOD-like receptor thermal protein domain associated protein 3 （NLRP3）， cleaved caspase-1 protein， and mRNA expressions of IL-1β，TNF-α， IL-6 and inducible nitric oxide synthase （iNOS） were all detected. RESULTS The prepared CPC-NPs had particle size of （675.69±64.58） nm， Zeta potential of （－20.11± E-mail：zhangleifang1986@163.com 0.98） mV， polydispersity coefficient of 0.455±0.010 （n＝3）；entrapment efficiency of 35.60%， and drug loading of 16.13%；CPC-NPs had regular spherical shapes， where the drug could be sustainably released for more than 30 hours. Compared with Mod group， the levels of T-AOC， SOD， CAT （excluding the 30 μg/mL group of CPC-NPs） and GSH-Px， mRNA expressions of CAT and GST， as well as the Bcl-2/Bax protein ratio and mRNA ratio were significantly increased in MLE-12 cells of different concentration groups of CPC-NPs， while MDA levels and caspase-3 protein and mRNA expression were significantly reduced （P＜0.01 or P＜0.05）. Compared with Mod group， the levels of IL-1β， TNF-α and IL-6， NLRP3 and cleaved-caspase-1 protein expressions， as well as the mRNA expressions of IL-1β， TNF-α， IL-6 and iNOS in RAW264.7 cells of different concentration groups of CPC-NPs were significantly reduced （P＜0.01 or P＜0.05）. CONCLUSIONS CPC-NPs with lung targeting and sustained release property were prepared successfully， which can alleviate acute lung injury induced by LPS combined with seawater through antioxidant stress， inhibiting cell apoptosis and inflammatory response.