Objective:To observe the tumor control and the degree of radiation-induced lung injury (RILI) between FLASH irradiation and conventional dose rate (CONV) irradiation, and compare the changes in plasma proteomic profiles of mice following whole-lung FLASH and CONV irradiation using proteomics method.Methods:A mouse model with metastatic lung cancer was established. After whole-lung irradiation, changes in normal lung capacity were monitored using CT scans. Then, a RILI model was constructed to examine pathological alterations in lung tissues following whole-lung CONV and FLASH irradiation. Plasma samples were collected from mice receiving whole-lung CONV irradiation ( n = 5) and whole-lung FLASH irradiation ( n = 5), followed by comparison with samples from the control group of healthy mice (also referred to as the healthy control group). These plasma samples were analyzed using isobaric tags for relative and absolute quantification (iTRAQ)-based proteomics, followed by the screening and identification of differentially expressed proteins using high-throughput bioinformatics. Moreover, protein-protein interaction (PPI) network analysis was conducted to identify hub genes using the STRING database and Cytoscape software. Results:Whole-lung FLASH and CONV irradiation produced consistent tumor control, with the former significantly reducing RILI compared to the latter. A total of 609 proteins were identified through proteomic analysis. Among them, 89 differentially expressed proteins were detected in the whole-lung FLASH group. Gene Ontology (GO) enrichment analysis indicated that up-regulated genes were primarily associated with stress and inflammatory responses, whereas down-regulated genes were related to ATP metabolism and angiogenesis regulation. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that up-regulated genes were predominantly enriched in unfolded protein response pathways, while down-regulated genes were mainly involved in metabolic pathways and oxidative phosphorylation. Integrated PPI analysis and subsequent validation via reverse transcription-polymerase chain reaction (RT-PCR) revealed four key genes.Conclusions:Compared to the whole-lung CONV irradiation, whole-lung FLASH irradiation reduces the RILI of normal lung tissues while maintaining equivalent tumor control in metastatic lung cancer. Proteomic analysis of differentially expressed proteins in plasma after whole-lung FLASH and CONV irradiation provides valuable insights into the molecular mechanisms underlying the FLASH effect.

Objective:To observe the tumor control and the degree of radiation-induced lung injury (RILI) between FLASH irradiation and conventional dose rate (CONV) irradiation, and compare the changes in plasma proteomic profiles of mice following whole-lung FLASH and CONV irradiation using proteomics method.Methods:A mouse model with metastatic lung cancer was established. After whole-lung irradiation, changes in normal lung capacity were monitored using CT scans. Then, a RILI model was constructed to examine pathological alterations in lung tissues following whole-lung CONV and FLASH irradiation. Plasma samples were collected from mice receiving whole-lung CONV irradiation ( n = 5) and whole-lung FLASH irradiation ( n = 5), followed by comparison with samples from the control group of healthy mice (also referred to as the healthy control group). These plasma samples were analyzed using isobaric tags for relative and absolute quantification (iTRAQ)-based proteomics, followed by the screening and identification of differentially expressed proteins using high-throughput bioinformatics. Moreover, protein-protein interaction (PPI) network analysis was conducted to identify hub genes using the STRING database and Cytoscape software. Results:Whole-lung FLASH and CONV irradiation produced consistent tumor control, with the former significantly reducing RILI compared to the latter. A total of 609 proteins were identified through proteomic analysis. Among them, 89 differentially expressed proteins were detected in the whole-lung FLASH group. Gene Ontology (GO) enrichment analysis indicated that up-regulated genes were primarily associated with stress and inflammatory responses, whereas down-regulated genes were related to ATP metabolism and angiogenesis regulation. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that up-regulated genes were predominantly enriched in unfolded protein response pathways, while down-regulated genes were mainly involved in metabolic pathways and oxidative phosphorylation. Integrated PPI analysis and subsequent validation via reverse transcription-polymerase chain reaction (RT-PCR) revealed four key genes.Conclusions:Compared to the whole-lung CONV irradiation, whole-lung FLASH irradiation reduces the RILI of normal lung tissues while maintaining equivalent tumor control in metastatic lung cancer. Proteomic analysis of differentially expressed proteins in plasma after whole-lung FLASH and CONV irradiation provides valuable insights into the molecular mechanisms underlying the FLASH effect.

Objective:To conduct a comparative analysis of the radiation damage to zebrafish embryos and the associated biological mechanism after ultra-high dose rate (FLASH) and conventional dose rate irradiation.Methods:Zebrafish embryos at 4 h post-fertilization were exposed to conventional and FLASH irradiation (9 MeV electron beam). The mortality and hatchability of zebrafish after radiation exposure were recorded. Larvae at 96 h post-irradiation underwent morphological scoring, testing of reactive oxygen species (ROS) levels, and analysis of changes in oxidative stress indicators.Results:Electron beam irradiation at doses of 2-12 Gy exerted subtle effects on the mortality and hatchability of zebrafish embryos. However, single high-dose irradiation (≥ 6 Gy) could lead to developmental malformation of larvae, with conventional irradiation showing the most significant effects ( t = 0.87-9.75, P < 0.05). In contrast, after FLASH irradiation (≥ 6 Gy), the ROS levels in zebrafish and its oxidative stress indicators including superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) were significantly reduced ( t = 0.42-15.19, P < 0.05). There was no statistically significant difference in ROS levels in incubating solutions after conventional and FLASH irradiation ( P > 0.05). Conclusions:Compared to conventional irradiation, FLASH irradiation can reduce radiation damage to zebrafish embryos, and this is in a dose-dependent manner. The two irradiation modes lead to different oxidative stress levels in zebrafish, which might be a significant factor in the reduction of radiation damage with FLASH irradiation.

Objective:To explore the relationship and dynamic changes between virological markers and hepatic pathological damage due to host anti-hepatitis B virus (HBV) immunity in the natural course of disease in chronic HBV infected patients.Methods:Two hundred and thirty-eight adult chronic HBV-infected patients who underwent liver biopsy from January 2016 to June 2022 in Taizhou Hospital, Zhejiang Province, were retrospectively selected. General clinical data such as age, gender, platelets, ALT, AST, albumin, HBV DNA, qHBsAg, HBeAg, and liver pathology diagnostic indexes such as the grade of liver necroinflammation and liver fibrotic stages of the patients were collected. The patients were grouped according to HBeAg status, and subgrouped according to different grades of liver necroinflammation and different HBV DNA loads. Statistical analyses were performed to compare the differences in HBV virologic marker levels between the groups, and the correlation between them and the indicators of hepatic inflammatory injury, such as ALT,AST, and the grade of liver necroinflammation in the patients.Results:The levels of HBV virological markers in HBeAg-positive patients with moderate or higher liver necroinflammatory grade (G≥2) were significantly lower than those with mild (no) liver necroinflammatory grade (G < 2) ( P < 0.01); whereas the opposite trend was observed in HBeAg-negative patients, with the levels of HBV DNA, and qHBsAg in the G≥2 subgroup being significantly higher than those in the G < 2 subgroup ( P < 0.01). Correspondingly, HBV DNA level and qHBsAg showed weak to moderately strong negative correlation with liver necroinflammatory grade and AST which was an indicator of hepatic inflammatory injury in HBeAg-positive patients ( P < 0.05); whereas in HBeAg-negative patients, they showed weak to moderately strong positive correlation with hepatic inflammatory activity and ALT, AST ( P < 0.001), in which qHBsAg showed only a weak positive correlation with patients' liver necroinflammatory grade ( P = 0.003). Further subgroup analyses of HBeAg-positive patients according to whether the HBV DNA level was > 2×10 6 IU/ml showed weak to moderate negative correlations between HBV virological markers and liver necroinflammatory grade as well as ALT and AST in the subgroup of patients with HBV DNA > 2×10 6 IU/ml ( P < 0.05); however, the negative correlation disappeared in patients who were still HBeAg positive and had HBV DNA ≤ 2×10 6 IU/ml. Moreover, HBV DNA and ALT, HBeAg and AST showed moderate positive correlation ( P < 0.05). Conclusion:We speculate that the activation of host anti-HBV immunity can efficiently inhibit HBV replication by targeting the infected hepatocytes, but only in the early phase of disease progression in HBeAg positive patients with HBV DNA high (> 2×10 6 IU/ml).

Objective:To compare the effects on DNA strand break induced by ultra-high dose rate (FLASH) electron beam and conventional irradiation, and investigate whether FLASH effect was correlated with a reduction of radiation response.Methods:Aqueous pBR322 plasmid was treated with FLASH (125 Gy/s) and conventional irradiation (0.05 Gy/s) under physioxia (4% O 2) and normoxia (21% O 2). Open circle DNA and linear DNA were detected by agarose gel electrophoresis, and the plasmid DNA damage was quantified with an established mathematical model to calculate the relative biological effect (RBE) of DNA damage. In some experiments, Samwirin A (SW) was applied to scavenge free radicals generated by ionizing radiation. Results:Under physioxia, the yields of DNA strand breakage induced by both FLASH and conventional irradiation had a dose-dependent manner. FLASH irradiation could significantly decrease radiation-induced linear DNA compared with conventional irradiation ( t=5.28, 5.79, 7.01, 7.66, P<0.05). However, when the aqueous plasmid was pretreated with SW, there was no difference of DNA strand breakage between FLASH and conventional irradiation ( P>0.05). Both of the yields of open circle DNA and linear DNA had no difference caused by FLASH and conventional radiotherapy at normoxia, but were significantly higher than those under physioxia. In addition, the yields of linear DNA and open circle DNA induced by FLASH irradiation per Gy were (2.78±0.03) and (1.85±0.17) times higher than those of conventional irradiation, respectively. Conclusions:FLASH irradiation attenuated radiation-induced DNA damage since a low production yield of free radical in comparison with conventional irradiation, and hence the FLASH effect was correlated with oxygen content.

Objective:To analyze the data of ultra-high dose rate (FLASH) radiotherapy in GEO (Gene Expression Omnibus) database by bioinformatics method, in order to find the hub genes involved in flash radiotherapy induced acute T-lymphoblastic leukemia.Methods:The gene expression profiles of malignant tumors receiving FLASH radiotherapy were downloaded from GEO database. The R software was used to screen the differential expressed genes (DEGs) and analyze their biological functions and signal pathways. The protein-protein interaction (PPI) network of DEGs was analyzed by online tool of STRING, and Hub genes were screened by Cytoscape plug-in. The expressions of screened Hub genes in acute T lymphoblastic leukemia were identified with TCGA (The Cancer Genome Atlas) and GTEx (Genotype-Tissue Expression) database.Results:Based on the analysis of GSE100718 microarray dataset of GEO database, a total of 12 800 genes were found to be associated with radiosensitivity of acute T lymphoblastic leukemia, of which 61 significantly altered DEGs were selected for further analysis. It was found that these genes were involved in the biological processes of metabolism, stress response, and immune response through the pathways of oxidative phosphorylation, unfolded protein response, fatty acid metabolism, and so on. PPI analysis indicated that HSPA5 and SCD belonged to the Hub genes involved in the regulation of FLASH radiosensitivity, and they were significantly highly expressed in acute T lymphoblastic leukemia combined with TRD/LMO2-fusion gene.Conclusions:Through bioinformatics analysis, the Hub genes involved in regulating the sensitivity of FLASH radiotherapy and conventional radiotherapy can be effectively screened, and thus the gene expression profiles can be used to guide the stratification of cancer patients to achieve a precise radiotherapy.

As a method for local treatment, radiotherapy plays a key role in the management of tumors. In the past few decades, great progress has been made in radiotherapy technology, with improvements in conformity, homogeneity, and radiotherapy efficiency, and the results are encouraging. Nevertheless, the maximum tolerated dose of normal tissue has limited the further increase in radiotherapy dose in the tumor area. If radiation-induced toxicities can be reduced, a higher radiotherapy dose can be delivered to tumor tissue, so as to achieve a better treatment response. In recent years, the unique FLASH effect of ultra-high-dose-rate radiotherapy (FLASH-RT) is capable of maintaining a consistent tumor response whilst reducing radiation-induced toxicities in normal tissue, and therefore, FLASH-RT has become a research hotspot in the field of radiotherapy across the world. At present, some scholars tend to explain the FLASH effect using the theory of acute oxygen depletion, but the protective effect of FLASH-RT on normal tissue remains to be clarified. In addition, preliminary clinical studies have been conducted for FLASH-RT, and the results are promising. Based on existing evidence, this article elaborates on the research advances in FLASH-RT in the treatment of malignant tumor, so as to provide a reference for the translation and application of this new technique.

The cytotoxic effect targeting hepatitis B virus (HBV) infected hepatocytes from virus-specific cytotoxic T cells and the neutralizing antibodies secreted by virus-specific B cells play an important role in the immune control and elimination of HBV. In patients with chronic hepatitis B, the liver immune microenvironment usually presents a suppression state, and virus-specific immune cells are mostly exhausted. Studies on the interaction between HBV and host immunity during infection, especially the influence of various viral proteins on immune cell function, will contribute to understanding the mechanism of the chronicity of HBV infection, disease progression, and optimization of immunotherapy against HBV. The review summarized the suppressive effects of HBV viral proteins on the host innate immunity and adaptive immune system, to help us understanding the mechanism(s) relevant to the observation that a CHB patient with HBeAg loss and lower HBsAg level is more likley achieving functionall cure. and expect to provide new sights for accelerate virus clearance and achieve functional cure of chronic hepatitis B, by removing the HBV viral proteins and consequently, liberting host immune from suppression state.

The first-line nucleos(t)ide analogs (NAs) based antiviral drugs can effectively inhibit HBV replication and slow down the progression of chronic hepatitis B. However, about 20% of patients receiving standard NAs antiviral therapy will still develop low-level viremia (LLV). Therefore, understanding the occurrence mechanism of LLV will help to optimize antiviral treatment regimens and improve the prognosis of patients with chronic hepatitis B. This article systematically summarizes the possible mechanisms of LLV occurrence, and the important factor of NAs failure. Taking into account the unique limitations of NAs competitive inhibition of virus replication, weakening host's immune response is not enough to directly eliminate infected hepatocytes. This makes it difficult to achieve a complete virological response in some patients with the active compensatory proliferation of residual infected hepatocytes and the accompanying effective removal or dilution of covalent, closed, circular DNA (cccDNA) pools. Therefore, it is speculated that activating host immunity can eliminate infected liver cells and may be more conducive to address LLV.

Objective:To investigate the clinical and diagnostic value of liver stiffness measurement (LSM) for the evaluation and comparison of aspartate aminotransferas/platelet ratio index (APRI), fibrosis 4 indexes (FIB-4) and NAFLD fibrosis score (NFS) with liver fibrosis staging in relation to nonalcoholic fatty liver disease (NAFLD).Methods:103 cases with NAFLD who met the inclusion criteria confirmed by liver biopsy were selected for retrospective analysis. The results of serological tests and LSM were recorded. The APRI, FIB-4 and NFS were calculated. The accuracy and applicability of four liver fibrosis models in the diagnosis of liver fibrosis in NAFLD patients were compared with the receiver operating characteristic curve (ROC), and the diagnostic cut-off value of LSM was established.Results:Varying degrees of LSM, APRI, FIB-4 and NFS had shown positive correlations with the increasing degree of liver fibrosis. Among them, LSM was positively correlated with the degree of liver fibrosis, and the correlation coefficient was r = 0.727, P < 0.0001. Consistent with this, the area under the receiver operating characteristic curve, sensitivity, and specificity of LSM diagnosis of liver fibrosis in different stages was significantly higher than APRI, FIB-4 and NFS. Area under receiver operating characteristic curve of LSM was 0.862 and 0.928 for significant liver fibrosis ( f ≥ 2), and advanced liver fibrosis ( f ≥ 3). Conclusion:LSM has a good diagnostic exclusion value for NAFLD-induced fibrosis, and its sensitivity and specificity are better than APRI, FIB-4 and NFS.