Objective:To investigate the current status of application of stereotactic body radiation therapy (SBRT) in China, aiming to provide reference for promoting the development of this technology.Methods:From January to March 2024, a questionnaire was designed and distributed online, targeting member units of the Professional Committee of Stereotactic Radiosurgery Treatment, which covers 175 radiotherapy units in 30 provinces and regions nationwide. The survey focused on the current application of SBRT technology and its utilization in the treatment of early-stage non-small cell lung cancer (NSCLC). A statistical description of the survey results was presented.Results:Of 175 questionnaires distributed, a total of 130 valid responses were collected, with an effective response rate of 74.3%. A total of 81.5% (106/130) of the units had implemented SBRT technology, and 99.1% of the respondents believed it was necessary to further promote SBRT technology, yet the actual training rate was only 67.0%. SBRT equipment configuration: there were a total of 267 SBRT equipment, featuring a diverse range of types, with traditional linear accelerators as the mainstays, accounting for 76.0% ( n=203), followed by 12.0% ( n=32) for TOMO, 6.4% ( n=17) for Cyber knife, 3.7% ( n=10) for Gamma knife, and proton/heavy ion equipment at 1.5% ( n=4), respectively. The percentage of units with multi-leaf collimator leaf widths ≤0.5 cm was 93.4% (99/106). The application of SBRT: the first radiotherapy unit commenced SBRT in 2000, and this technology entered a period of rapid growth after 2015, sustaining a steady increase over the past decade; SBRT technology was mainly applied in the brain, lung, liver, bone, adrenal gland, and kidney, with application rates of 97.2%, 94.3%, 86.8%, 71.7%, 56.6%, and 27.4%, respectively, while the application rates for the pancreas, metastatic lymph nodes, and other parts were less than 5%. Current status of SBRT technology application in early-stage NSCLC: 90.6% (96/106) of units had implemented SBRT; pre-treatment multi-disciplinary diagnosis and treatment accounted for 77% (74/96); the proportion of application units for peripheral and central type lung cancer lesions both exceeded 57.3%, whereas the application rate for ultra-central type and lesions > 5 cm lung cancer was less than 30%; there was significant variability in the selection of reference guidelines, dose fractionation patterns, and the concept of central type among units. Conclusions:The development of SBRT technology in China is in a period of steady growth, but several issues such as low training rate and lack of standardization still exist. The survey results provide important reference for clinical training and promotion of SBRT technology in China.

To perform the phylogenetic characterization of an isolated porcine rotavirus(PoRV)and investigate its pathogenicity in suckling mice and piglets.A G4P[23]genotype PoRV strain JSJR2023 was successfully isolated from the diarrheic piglet feces through propagation in MA104 cells.The viral proliferation kinetics were analyzed using TCID50 assays,followed by complete genome sequencing through Sanger sequencing platforms.Comprehensive genotyping and phylogenetic reconstruction were conducted using MEGA7.0 with maximum likelihood algorithms.Pathogenicity was assessed in the following animal models:5-day-old C57BL/6 mice and 3-day-old piglets.Multidimensional evaluation included clinical monitoring(diarrhea scoring,growth parameters),virological detection,and histopathological analysis of intestinal tissues.The virus strain JSJR2023 could replicate efficiently in MA104 cells,achieving peak titers of 107.5 TCID50/mL.Whole genome genotype analysis showed that the strain belonged to G4-P[23]-I5-R1-C1-M1-A8-N1-T1-E1-H1.Phylogenetic analysis indicated that the VP3 and NSP4 genes of JSJR2023 strain were most closedrelated to human species rotaviruses,suggesting genetic reassortment between human and porcine RV strains.The animal experiments in suckling mice showed that the JSJR2023 strain infection caused diarrhea symptoms,intestinal edema and congestion,and shedding of intestinal villus epithelial cells.The pathogenicity experiments in piglets showed that compared with the control group,the challenged group of pig-lets had severe diarrhea symptoms,accompanied by reduced appetite and listlessness.Post-mortem examination revealed that the intes-tines were significantly thinner,congested,and filled with yellow watery contents.The challenged piglets showed typical pathological changes such as thinning of the intestinal wall and shortening and shedding of intestinal villi.In conclusion,this study successfully iso-lated a human-porcine recombinant G4P[23]PoRV strain and established the infection models in suckling mice and piglets,providing important tools for investigating the pathogenic mechanism of PoRV,evaluating vaccines and developing antiviral drug.

Objective:To reveal the differences in the transcriptome maps of brain tissues in mice subjected to Flash irradiation and conventional dose rate irradiation with electron beams and to explain the biological effect and mechanisms of Flash irradiation from multiple perspectives.Methods:Following the principle of grouping based on approximate body weights, 36 female C57BL/6J mice were divided into three groups, i. e., the control, conventional dose rate irradiation (CONV), and Flash irradiation (Flash) groups, with 12 mice in each group. Both the CONV and Flash groups received a single 15 Gy whole-brain irradiation with 9 MeV electron beams. At 3 d post-irradiation, the whole-brain tissue specimens were collected for hematoxylin-eosin (HE) staining to observe pathological changes. At 1, 3, and 10 weeks post-irradiation, the motion function, cognitive ability, depression level, and spatial memory capacity of the mice were assessed using ethology. At 1 and 10 weeks after behavioral experiments, brain tissue samples were collected and snap-frozen in liquid nitrogen for reference-based transcriptome sequencing. Accordingly, the differences in the transcriptome maps of radiation-induced brain injury between CONV and Flash groups were analyzed.Results:The HE staining-based pathological result revealed that compared to the CONV group, the Flash group exhibited reduced glial cell hyperplasia and inflammatory cell infiltration in brain tissues. Ethological research result at 1 week post-irradiation showed that the CONV group manifested a significantly decreased total traveled distance compared to the control and Flash groups ( t = 5.51, 2.38, P < 0.05) and a significantly increased immobility time compared to the control group ( t = 3.60, P < 0.05). Ethological research result at 3 weeks post-irradiation indicated that compared to the CONV group, the Flash group displayed significantly alleviated cognitive impairment ( t = 3.35, P < 0.05) and reduced depression levels ( t = 2.39, P < 0.05). Ethological research result at 10 weeks post-irradiation demonstrated that the CONV group showed the worst cognitive performance, significantly differing from the control group ( t = 4.53, P < 0.05). Transcriptome sequencing result revealed that besides immune-related pathways, the Flash group also exhibited multiple upregulated metabolic pathways and fibroblast growth factor (FGF)-related pathways compared to the CONV group. Conclusions:Compared to conventional dose rate irradiation, Flash irradiation can effectively alleviate radiation-induced brain injury in mice. This effect is associated with various metabolic pathways (including amino acid metabolism) and FGF-related pathways besides immune pathways.

Objective To compare image quality and clinical usefulness between single breath-hold three-dimensional magnetic resonance cholangiopancreatography with compressed sensing(3D BH-CS-MRCP)and with gradient and spin-echo(3D BH-GRASE-MRCP)and conventional three-dimensional breath-triggered magnetic resonance cholangiopancreatography(3D RT-MRCP).Methods A retrospective analysis was performed in 48 patients(26 males and 22 females,mean age of 53.14±15.19 years),who underwent 3D BH-GRASE-MRCP,3D BH-CS-MRCP and 3D RT-MRCP from September to December 2023.Pancreaticobiliary duct visibility,motion artifacts,background suppression,and overall image quality were scored on a 5-point scale by two radiologists.The relative contrast ratio of three bile duct segmentations(common bile duct,left and right intrahepatic bile ducts)were calculated,and the acquisition time of the three sequences was recorded.Friedman test with a post-hoc test was performed to compare image acquisition time,qualitative and quantitative results.Results The acquisition time was significantly shorter in the two breath-hold groups than for conventional 3D RT-MRCP(P＜0.001).There were no significant differences in overall image quality,motion artifacts,common bile duct and primary branch of intrahepatic bile duct among the three groups.The relative contrast ratio,intrahepatic biliary secondary branch visibility and background suppression score of 3D RT-MRCP and BH-CS-MRCP were significantly higher than those of BH-GRASE-MRCP(P＜0.01).The pancreatic duct(proximal,middle,distal)visibility score of 3D RT-MRCP was significantly better than that of BH-GRASE-MRCP(P=0.002,0.043,0.001),but the gallbladder and gallbladder duct visibility score of BH-GRASE-MRCP was higher than that of 3D RT-MRCP(P=0.036).There was no significant difference between 3D RT-MRCP and BH-CS-MRCP scores except for the middle and distal pancreatic duct visibility.Conclusion Breath-hold 3D MRCP with GRASE and CS can give us feasible options for pancreaticobiliary diagnosis,which significantly shortens the acquisition time without reducing the overall image quality.Compared with BH-GRASE-MRCP,BH-CS-MRCP has better consistency in pancreaticobiliary duct visibility and background suppression.

Objective To compare image quality and clinical usefulness between single breath-hold three-dimensional magnetic resonance cholangiopancreatography with compressed sensing(3D BH-CS-MRCP)and with gradient and spin-echo(3D BH-GRASE-MRCP)and conventional three-dimensional breath-triggered magnetic resonance cholangiopancreatography(3D RT-MRCP).Methods A retrospective analysis was performed in 48 patients(26 males and 22 females,mean age of 53.14±15.19 years),who underwent 3D BH-GRASE-MRCP,3D BH-CS-MRCP and 3D RT-MRCP from September to December 2023.Pancreaticobiliary duct visibility,motion artifacts,background suppression,and overall image quality were scored on a 5-point scale by two radiologists.The relative contrast ratio of three bile duct segmentations(common bile duct,left and right intrahepatic bile ducts)were calculated,and the acquisition time of the three sequences was recorded.Friedman test with a post-hoc test was performed to compare image acquisition time,qualitative and quantitative results.Results The acquisition time was significantly shorter in the two breath-hold groups than for conventional 3D RT-MRCP(P＜0.001).There were no significant differences in overall image quality,motion artifacts,common bile duct and primary branch of intrahepatic bile duct among the three groups.The relative contrast ratio,intrahepatic biliary secondary branch visibility and background suppression score of 3D RT-MRCP and BH-CS-MRCP were significantly higher than those of BH-GRASE-MRCP(P＜0.01).The pancreatic duct(proximal,middle,distal)visibility score of 3D RT-MRCP was significantly better than that of BH-GRASE-MRCP(P=0.002,0.043,0.001),but the gallbladder and gallbladder duct visibility score of BH-GRASE-MRCP was higher than that of 3D RT-MRCP(P=0.036).There was no significant difference between 3D RT-MRCP and BH-CS-MRCP scores except for the middle and distal pancreatic duct visibility.Conclusion Breath-hold 3D MRCP with GRASE and CS can give us feasible options for pancreaticobiliary diagnosis,which significantly shortens the acquisition time without reducing the overall image quality.Compared with BH-GRASE-MRCP,BH-CS-MRCP has better consistency in pancreaticobiliary duct visibility and background suppression.

Objective To investigate the effect of ventilation with different tidal volumes on respiratory mechanics and haemodynamics in children with severe pneumonia.Methods A total of 104 children with severe pneumonia were divided into the control group and the observation group using a random number table method,with 52 cases in each group.Both groups underwent mechanical ventilation treatment.The control group was treated with conventional tidal volume of 10-12 mL/kg,while the observation group was given a low tidal volume of 6-8 mL/kg.The respiratory mechanics indicators,hemodynamic indicators and inflammatory factor indicators before and after treatment were compared between the two groups.Results After treatment,the airway resistance(AR)and airway closing pressure(AOP)were lower in the observation group than those of the control group(P＜0.05),and pulmonary dynamic compliance(Cdyn)was higher in the observation group than that of the control group(P＜0.05).There were no significant differences in heart rate(HR),mean arterial pressure(MAP)and central venous pressure(CVP)after treatment between the two groups(P＜0.05).After treatment,the levels of interleukin(IL)-6,IL-8 and tumor necrosis factor-α(TNF-α)were all lower in the observation group than those in the control group(P＜0.05).Conclusion Small tidal volume mechanical ventilation is effective in improving the respiratory mechanics of children with severe pneumonia without causing large fluctuations in their hemodynamics.At the same time,it can reduce the level of inflammatory factors in the organism.

Objective To investigate the effect of ventilation with different tidal volumes on respiratory mechanics and haemodynamics in children with severe pneumonia.Methods A total of 104 children with severe pneumonia were divided into the control group and the observation group using a random number table method,with 52 cases in each group.Both groups underwent mechanical ventilation treatment.The control group was treated with conventional tidal volume of 10-12 mL/kg,while the observation group was given a low tidal volume of 6-8 mL/kg.The respiratory mechanics indicators,hemodynamic indicators and inflammatory factor indicators before and after treatment were compared between the two groups.Results After treatment,the airway resistance(AR)and airway closing pressure(AOP)were lower in the observation group than those of the control group(P＜0.05),and pulmonary dynamic compliance(Cdyn)was higher in the observation group than that of the control group(P＜0.05).There were no significant differences in heart rate(HR),mean arterial pressure(MAP)and central venous pressure(CVP)after treatment between the two groups(P＜0.05).After treatment,the levels of interleukin(IL)-6,IL-8 and tumor necrosis factor-α(TNF-α)were all lower in the observation group than those in the control group(P＜0.05).Conclusion Small tidal volume mechanical ventilation is effective in improving the respiratory mechanics of children with severe pneumonia without causing large fluctuations in their hemodynamics.At the same time,it can reduce the level of inflammatory factors in the organism.

To perform the phylogenetic characterization of an isolated porcine rotavirus(PoRV)and investigate its pathogenicity in suckling mice and piglets.A G4P[23]genotype PoRV strain JSJR2023 was successfully isolated from the diarrheic piglet feces through propagation in MA104 cells.The viral proliferation kinetics were analyzed using TCID50 assays,followed by complete genome sequencing through Sanger sequencing platforms.Comprehensive genotyping and phylogenetic reconstruction were conducted using MEGA7.0 with maximum likelihood algorithms.Pathogenicity was assessed in the following animal models:5-day-old C57BL/6 mice and 3-day-old piglets.Multidimensional evaluation included clinical monitoring(diarrhea scoring,growth parameters),virological detection,and histopathological analysis of intestinal tissues.The virus strain JSJR2023 could replicate efficiently in MA104 cells,achieving peak titers of 107.5 TCID50/mL.Whole genome genotype analysis showed that the strain belonged to G4-P[23]-I5-R1-C1-M1-A8-N1-T1-E1-H1.Phylogenetic analysis indicated that the VP3 and NSP4 genes of JSJR2023 strain were most closedrelated to human species rotaviruses,suggesting genetic reassortment between human and porcine RV strains.The animal experiments in suckling mice showed that the JSJR2023 strain infection caused diarrhea symptoms,intestinal edema and congestion,and shedding of intestinal villus epithelial cells.The pathogenicity experiments in piglets showed that compared with the control group,the challenged group of pig-lets had severe diarrhea symptoms,accompanied by reduced appetite and listlessness.Post-mortem examination revealed that the intes-tines were significantly thinner,congested,and filled with yellow watery contents.The challenged piglets showed typical pathological changes such as thinning of the intestinal wall and shortening and shedding of intestinal villi.In conclusion,this study successfully iso-lated a human-porcine recombinant G4P[23]PoRV strain and established the infection models in suckling mice and piglets,providing important tools for investigating the pathogenic mechanism of PoRV,evaluating vaccines and developing antiviral drug.

Objective:To reveal the differences in the transcriptome maps of brain tissues in mice subjected to Flash irradiation and conventional dose rate irradiation with electron beams and to explain the biological effect and mechanisms of Flash irradiation from multiple perspectives.Methods:Following the principle of grouping based on approximate body weights, 36 female C57BL/6J mice were divided into three groups, i. e., the control, conventional dose rate irradiation (CONV), and Flash irradiation (Flash) groups, with 12 mice in each group. Both the CONV and Flash groups received a single 15 Gy whole-brain irradiation with 9 MeV electron beams. At 3 d post-irradiation, the whole-brain tissue specimens were collected for hematoxylin-eosin (HE) staining to observe pathological changes. At 1, 3, and 10 weeks post-irradiation, the motion function, cognitive ability, depression level, and spatial memory capacity of the mice were assessed using ethology. At 1 and 10 weeks after behavioral experiments, brain tissue samples were collected and snap-frozen in liquid nitrogen for reference-based transcriptome sequencing. Accordingly, the differences in the transcriptome maps of radiation-induced brain injury between CONV and Flash groups were analyzed.Results:The HE staining-based pathological result revealed that compared to the CONV group, the Flash group exhibited reduced glial cell hyperplasia and inflammatory cell infiltration in brain tissues. Ethological research result at 1 week post-irradiation showed that the CONV group manifested a significantly decreased total traveled distance compared to the control and Flash groups ( t = 5.51, 2.38, P < 0.05) and a significantly increased immobility time compared to the control group ( t = 3.60, P < 0.05). Ethological research result at 3 weeks post-irradiation indicated that compared to the CONV group, the Flash group displayed significantly alleviated cognitive impairment ( t = 3.35, P < 0.05) and reduced depression levels ( t = 2.39, P < 0.05). Ethological research result at 10 weeks post-irradiation demonstrated that the CONV group showed the worst cognitive performance, significantly differing from the control group ( t = 4.53, P < 0.05). Transcriptome sequencing result revealed that besides immune-related pathways, the Flash group also exhibited multiple upregulated metabolic pathways and fibroblast growth factor (FGF)-related pathways compared to the CONV group. Conclusions:Compared to conventional dose rate irradiation, Flash irradiation can effectively alleviate radiation-induced brain injury in mice. This effect is associated with various metabolic pathways (including amino acid metabolism) and FGF-related pathways besides immune pathways.

Objective:To investigate the current status of application of stereotactic body radiation therapy (SBRT) in China, aiming to provide reference for promoting the development of this technology.Methods:From January to March 2024, a questionnaire was designed and distributed online, targeting member units of the Professional Committee of Stereotactic Radiosurgery Treatment, which covers 175 radiotherapy units in 30 provinces and regions nationwide. The survey focused on the current application of SBRT technology and its utilization in the treatment of early-stage non-small cell lung cancer (NSCLC). A statistical description of the survey results was presented.Results:Of 175 questionnaires distributed, a total of 130 valid responses were collected, with an effective response rate of 74.3%. A total of 81.5% (106/130) of the units had implemented SBRT technology, and 99.1% of the respondents believed it was necessary to further promote SBRT technology, yet the actual training rate was only 67.0%. SBRT equipment configuration: there were a total of 267 SBRT equipment, featuring a diverse range of types, with traditional linear accelerators as the mainstays, accounting for 76.0% ( n=203), followed by 12.0% ( n=32) for TOMO, 6.4% ( n=17) for Cyber knife, 3.7% ( n=10) for Gamma knife, and proton/heavy ion equipment at 1.5% ( n=4), respectively. The percentage of units with multi-leaf collimator leaf widths ≤0.5 cm was 93.4% (99/106). The application of SBRT: the first radiotherapy unit commenced SBRT in 2000, and this technology entered a period of rapid growth after 2015, sustaining a steady increase over the past decade; SBRT technology was mainly applied in the brain, lung, liver, bone, adrenal gland, and kidney, with application rates of 97.2%, 94.3%, 86.8%, 71.7%, 56.6%, and 27.4%, respectively, while the application rates for the pancreas, metastatic lymph nodes, and other parts were less than 5%. Current status of SBRT technology application in early-stage NSCLC: 90.6% (96/106) of units had implemented SBRT; pre-treatment multi-disciplinary diagnosis and treatment accounted for 77% (74/96); the proportion of application units for peripheral and central type lung cancer lesions both exceeded 57.3%, whereas the application rate for ultra-central type and lesions > 5 cm lung cancer was less than 30%; there was significant variability in the selection of reference guidelines, dose fractionation patterns, and the concept of central type among units. Conclusions:The development of SBRT technology in China is in a period of steady growth, but several issues such as low training rate and lack of standardization still exist. The survey results provide important reference for clinical training and promotion of SBRT technology in China.