Objective To investigate the advantages and disadvantages of percutaneous bone marrow puncture biopsy guided by automatic laser navigation and free-hand percutaneous bone marrow biopsy guided by CT.Methods Seventy patients with bone marrow biopsy at the department of nuclear medicine in this hos-pital from January to June 2022 were selected as the study subjects and divided into the laser navigation group (bone marrow biopsy guided by automatic laser navigation,n=30) and free-hand puncture group (percutane-ous bone marrow biopsy guided by CT,n=40) based on different guidance methods.The duration of the pro-cedure,total radiation dose,total number of scans,positive rate of bone lesion biopsy and puncture complica-tions occurrence were compared between the two groups.Results Compared to the free-hand puncture group,the operation duration in the laser navigation group was shorter[11.00(7.00,13.00)min vs. 13.00(11.00,17.75)min],the total radiation dose was lower[439.00(291.00,568.75)mGy vs. 510.00(431.25,708.50) mGy],total number of scans was less[4.50(3.00,6.00)times vs. 6.00(5.00,7.00)times],and the differ-ences were statistically significant (P<0.05).There was no statistically significant difference in the positive rate of bone lesion biopsy between the laser navigation group and free-hand puncture group[96.67％(29/30) vs. 85.00％(34/40),P>0.05].No puncture complications occurred in both groups.Conclusion Automatic laser navigation could assist the operators to better complete percutaneous bone marrow biopsy procedures.

Objective To investigate the effect of progesterone receptor membrane component 1(PGRMC1)mediated autophagy on the sensitivity of liver cancer cells to 125I particles irradiation.Methods Hepatoma cell lines Huh7 and LM3 were exposed to different doses(0,2,4,6 and 8 Gy)of 125I particles,and cell autophagy was observed by transmission electron microscopy(TEM).Then,autophagy inhibitor chloroquine(CQ),agonist rapamycin(Rapa),and PGRMC1 inhibitor AG-205 were used respectively to verify that PGRMC1-mediated autophagy plays a key role in the sensitivity of hepatocellular carcinoma cells to 125I particle irradiation.Cell proliferation,colony formation and apoptosis were detected by CCK-8 assay,clonal formation test and flow cytometry,respectively.The expression levels of PGRMC1,microtubule-associated protein light chain 3-Ⅰ(LC3-Ⅰ),LC3-Ⅱ and p62 were detected by Western blotting.Results Different doses of 125I particles irradiation significantly decreased the proliferation and clonogenesis of Huh7 and LM3 cells(P＜0.05),and increased the apoptotic cells(P＜0.01),in a dose-dependent manner.Compared with the 0 Gy group,the ratio of LC3-Ⅱ/LC3-Ⅰ in Huh7 and LM3 cells was obviously increased,and the expression of p62 was significantly down-regulated in the 6 Gy group.The proliferation capacity and clonal formation ability of Huh7 and LM3 cells were decreased significantly,and their apoptotic cells were increased notably in the 6 Gy+CQ group than the 6 Gy group,while the above results were on the contrary in the 6 Gy+Rapa group.The 6 Gy+AG205 group had notably decreased LC3-Ⅱ/LC3-Ⅰ ratio in the Huh7 and LM3 cells,up-regulated p62 expression,reduced cell proliferation capacity and clone formation ability,and enhanced cell apoptosis when compared with the 6 Gy group,and the above results of the 6 Gy+PGRMC1 group were opposite.Conclusion Increment of PGRMC1 induced by 125I irradiation can promote autophagy,increase the proliferation and clonogenesis,and reduce the apoptosis in hepatocellular carcinoma cells.

Small interfering RNA(siRNA) has been the focus of attention in the field of drug development for its excellent properties such as efficiency, specificity and transient nature in treating diseases. However, the poor stability and low cellular uptake of naked siRNAs make it difficult for them to exert their gene silencing effects, a high-quality drug delivery system is needed to deliver them to target cells where they can function. Many nano delivery systems are no longer suitable for siRNA transport due to toxicity and drug loading problems, chitosan derivatives are beginning to receive widespread attention because of their high water solubility, safety and stability. This paper reviewed the research progress of chitosan derivatives as siRNA nano-delivery systems and provided a reference for researchers who are interested in the development of nano-delivery systems.