Objective:To observe the presence or absence of necroptosis in PC12 cells after radiation injury, and to detect the expression of receptor-interacting protein 3(RIP3) and evaluate its regulatory effect on necroptosis.Methods:PC12 cells were treated with different doses of irradiation and their necroptosis was detected by lactate dehydrogenase (LDH) release at different time points. After pretreatment with necroptosis inhibitor Necrostatin-1(Nec-1), the changes of cell necroptosis were detected by LDH. The expression level of RIP3 after irradiation intervention was detected by Western blot (WB). After pretreatment with the RIP3-specific inhibitor GSK′872, the changes of cell necroptosis were detected by LDH. The best transfection sequence of RIP3 knockout was screened by WB. The cells were divided into the control group, irradiation group, solvent control group, no-load control group and pretreatment group. WB, immunofluorescence staining, MTT, LDH and Annex V-fluorescein Isothiocyanate/Propidium Iodide (AnnexV-FITC/PI) flow cytometry were used for detection and analysis.Results:After 4 Gy irradiation, the degree of cell necrosis was the highest after 3 hours of culture, and the expression level of RIP3 protein was up-regulated. The cell necrosis was decreased after Nec-1, GSK′872 and RIP3 gene knockdown pretreatment.Conclusions:The radiation injury of 4 Gy can induce the necroptosis of PC12 cells, and the most significant effect can be observed when cultured for 3 hours after irradiation. RIP3 is involved in the process of necroptosis of PC12 cells induced by radiation injury, and plays a pivotal positive regulatory role.

Objective:To investigate the current status and quality and safety of radiation therapy resources in medical institutions in Hunan province.Methods:The basic situation questionnaire, quality and safety self-assessment form were designed according to the content of the survey, distributed and recovered through the network, and the survey was conducted on all medical institutions (excluding military hospitals) conducting radiotherapy in Hunan province in 2022, and the quality and safety evaluation was checked by the Hunan Radiotherapy Quality Control Center using stratified sampling field inspection. The differences between the self-evaluation scores of radiotherapy quality and safety and the on-site inspection scores of each unit was compared using Wilcoxon test.Results:By the end of 2022, there were 76 medical institutions (excluding military hospitals) conducting radiotherapy in Hunan province, including 62 tertiary hospitals and 14 secondary hospitals, with a total of 44 253 radiotherapy patients admitted annually. The total number of personnel engaged in radiotherapy was 1 381, including 746 physicians, 205 physicists, 397 technicians and 33 maintenance engineers. There were a total of 88 accelerators (including 3 tomotherapy units), 10 gamma knives, and 28 rear-loading machines, with 1.33 gas pedals per million population. There were 36 units that were carrying out three-dimensional conformal technology, 60 static intensity modulation technology, 20 volumetric rotational intensity modulation, 27 stereotactic radiotherapy, 44 image-guided radiotherapy, 33 respiratory motion management, and 27 rear-loading radiotherapy. In the quality and safety evaluation situation, the basic requirements of radiotherapy specialty scored high, with 2 units achieving full marks and no failing units. Radiotherapy personnel and organization, radiotherapy process, documentation record score and other aspects of no full-score units, the score was concentrated in 60~＜80 points, and all have part of the unit failed.Conclusions:The radiotherapy industry in Hunan province has been developed steadily in recent years in general, and the structure of radiotherapy personnel tends to be reasonable, but there still exists uneven distribution of radiotherapy resources, poor utilization of equipment in some areas, and inadequate development of technology. The overall quality and safety evaluation are good, but there are still many deficiencies in the organizational requirements of radiotherapy personnel, process requirements and documentation, which need to be continuously optimized and improved in the future, and at the same time, field inspections will be intensified to ensure the quality and safety of radiotherapy.

Although the development of COVID-19 vaccines has been a remarkable success, the heterogeneous individual antibody generation and decline over time are unknown and still hard to predict. In this study, blood samples were collected from 163 participants who next received two doses of an inactivated COVID-19 vaccine (CoronaVac®) at a 28-day interval. Using TMT-based proteomics, we identified 1,715 serum and 7,342 peripheral blood mononuclear cells (PBMCs) proteins. We proposed two sets of potential biomarkers (seven from serum, five from PBMCs) at baseline using machine learning, and predicted the individual seropositivity 57 days after vaccination (AUC = 0.87). Based on the four PBMC's potential biomarkers, we predicted the antibody persistence until 180 days after vaccination (AUC = 0.79). Our data highlighted characteristic hematological host responses, including altered lymphocyte migration regulation, neutrophil degranulation, and humoral immune response. This study proposed potential blood-derived protein biomarkers before vaccination for predicting heterogeneous antibody generation and decline after COVID-19 vaccination, shedding light on immunization mechanisms and individual booster shot planning.
Humans ; COVID-19 Vaccines ; Leukocytes, Mononuclear ; Proteomics ; COVID-19/prevention & control* ; Vaccination ; Antibodies ; Antibodies, Viral ; Antibodies, Neutralizing