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1.
China Journal of Endoscopy ; (12): 31-40, 2024.
文章 在 中文 | WPRIM | ID: wpr-1024826

摘要

Objective To study the effect of spectrum irradiation combined with operative laparoscopy on inflammatory reaction and immune function in children with appendicitis.Methods 120 children with appendicitis from January 2022 to January 2023 were selected as the study subjects,randomly divided them into two groups using a random number table method:the control group(n = 60)and the study group(n = 60).The control group underwent laparoscopic minimally invasive appendectomy,and the study group underwent spectrum irradiation combined with laparoscopic minimally invasive appendectomy.The two groups compared perioperative recovery,procalcitonin(PCT),C-reactive protein(CRP)level,cellular immune function(CD4+,CD8+,and CD4+/CD8+),humoral immune function[immunoglobulin M(IgM),immunoglobulin G(IgG),C3,and C4],pain visual analogue scale(VAS),Alvarado score,and treatment effect and postoperative complication rate.Results Compared with the control group,the study group showed a significant reduction in the time to first anal exhaust and hospital stay after surgery,the differences were statistically significant(P<0.05).Compared with preoperative levels,the levels of PCT and CRP in both groups of patients increased at 12 and 24 h postoperatively,with the highest levels occurring at 12 h postoperatively;The PCT and CRP levels in the study group were lower than those in the control group at 12 and 24 h after surgery,the differences were statistically significant(P<0.05).Compared with preoperative data,the CD4+,CD8+,and CD4+/CD8+ levels decreased in both groups at 12 and 24 h postoperatively,with the lowest levels observed at 12 h postoperatively;The CD4+,CD8+,and CD4+/CD8+ levels in the study group were higher than those in the control group at 12 and 24 h after surgery,the differences were statistically significant(P<0.05).Compared with preoperative levels,the levels of IgM,IgG,C3,and C4 in both groups of patients decreased after surgery,with the lowest levels occurring 12 h after surgery;The levels of IgM,IgG,C3,and C4 in the study group were higher than those in the control group at 12 and 24 h after surgery,the differences were statistically significant(P<0.05).Compared with preoperative conditions,the VAS and Alvarado scores in both groups of patients decreased at 12 and 24 h after surgery.The VAS and Alvarado scores of the study group were lower than those of the control group at 12 and 24 h after surgery,the differences were statistically significant(P<0.05).Compared with the control group,the study group had a higher overall effective rate and a lower total incidence of complications,the differences were statistically significant(P<0.05).Conclusion Spectrum irradiation combined with operative laparoscopy can reduce postoperative inflammatory reaction,and improve immune function in children with appendicitis,shorten inflammatory reaction and immunosuppression time,reduce pain,and have a low incidence of postoperative complications,with ideal effect.

2.
文章 在 中文 | WPRIM | ID: wpr-1026205

摘要

Objective To investigate the feasibility of AccuLearning system for the auto-segmentation of target areas and organs-at-risk(OAR)for total marrow and lymphoid irradiation(TMLI)in children.Methods Thirty pediatric patients who underwent TMLI since 2018 to 2022 were selected.The patients were immobilized in the supine position,and their CT images were acquired on the Philips Brilliance Big Bore CT scanner.After the target areas and OAR were manually delineated and modified,the CT images and manually delineated contours were imported into AccuLearning system for training,validation,and testing of the auto-segmentation model.The auto-segmentation results in 6 TMLI patients in the test set were evaluated in terms of Dice similarity coefficient(DSC),95%Hausdorff distance and average surface distance.Results On the test set with 6 cases,except for the lens that was difficult to be delineated automatically,the DSC values was above 0.70 for all other target areas and OAR,with only one patient having a DSC value of 0.59 for the stomach.The average DSC value for the stomach in all 6 patients was 0.76,and the average DSC values for the other organs were above 0.80.Conclusion The target areas and OAR automatically delineated with the model can meet the requirements of clinical planning after simple modifications.

3.
文章 在 中文 | WPRIM | ID: wpr-1027406

摘要

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.

4.
文章 在 中文 | WPRIM | ID: wpr-1027408

摘要

Objective:To construct a three-dimensional time-dose-response model for dose estimation and validate its feasibility.Methods:Based on a random number table, mice were divided into 0, 2, 4, 6, and 8 Gy groups for whole-body X-ray irradiation, with each group consisting of three mice. Hair follicle cells of whiskers were sampled at 1, 6, and 24 h after the irradiation. After immunofluorescence staining, the numbers of γ-H2AX foci at different time points from 1 to 24 h post-irradiation were observed using a confocal laser scanning microscope. The average numbers of γ-H2AX foci observed were corrected using the Dolphin’s model, followed by the fitting of dose-response curves. Using the R software, the equations and surfaces of the three-dimensional model for partial-body irradiation were established using the irradiation doses, post-irradiation time, and the corrected average numbers of γ-H2AX foci.Results:The average number of γ-H2AX foci increased with dose at fixed time points 1, 6, and 24 h but decreased with irradiation time at fixed doses 2, 4, 6, and 8 Gy. The dose-response curve equations of partial-body irradiation were fitted as follows: YF = 2.853+ 3.775 D, R2= 0.928, at 1 h after the irradiation; YF = 0.144+ 2.775 D, R2= 0.903, at 6 h after the irradiation; YF = 0.066+ 2.472 D, R2= 0.85, at 24 h after the irradiation. The three-dimensional model equation fitted was YF = 6.837 t-1.728+ 3.113 t-0.071D, R2=0.897. Substituting different post-irradiation time points into the three-dimensional surface model appeared as a two-dimensional linear model. By substituting the number of γ-H2AX foci and irradiation time into the linear and the three-dimensional models, both models yielded relative deviations between the estimated and actual radiation doses of 30% or less. Conclusions:The three-dimensional time-dose-response model, established by using the number of γ-H2AX foci to estimate partial-body irradiation doses, can be preliminarily applied for dose estimation at all time points 1-24 h after irradiation.

5.
文章 在 中文 | WPRIM | ID: wpr-1027491

摘要

Objective:To analyze the treatment efficacy, safety and dose parameters of optimized hippocampus-avoidance prophylactic cranial irradiation (HA-PCI) in limited-stage small cell lung cancer (LS-SCLC) and explore the corresponding dosimetric parameters under the condition of narrowing the hippocampus avoidance region as hippocampus region plus 2 mm in three dimensions.Methods:Clinical data of patients with LS-SCLC receiving HA-PCI (hippocampus avoidance region defined as hippocampus region plus 2 mm in three dimensions) in Cancer Hospital Chinese Academy of Medical Sciences from August 2014 to June 2020 were retrospectively analyzed. Dose parameters of HA-PCI and adverse events were analyzed using descriptive statistics analysis. Changes of neurocognitive function, such as mini-mental state examination (MMSE) and Hopkins verbal learning test-revised (HVLT-R) scores, were evaluated by analysis of variance and Kruskal-Wallis H test. Overall survival (OS), progression-free survival (PFS) and intracranial PFS (iPFS) were calculated using Kaplan-Meier method. The cumulative incidence of local-regional recurrence (LRR), extracranial distant metastases (EDM), and locoregional recurrence (LR) were investigated under competing risk analysis. Results:A total of 112 patients were included, the median follow-up time was 50 months (95% CI: 45.61-54.38). The median volume of hippocampus was 4.85 ml (range: 2.65-8.34 ml), with the average dose ≤9 Gy in 106 patients (94.6%), ≤8 Gy in 92 patients (82.1%). The median volume of hippocampus avoidance area was 15.00 ml (range: 8.61-28.06 ml), with the average dose ≤12 Gy in 109 patients (97.3%), ≤10 Gy in 101 patients (90.2%). The 2-year cumulative LRR, EDM, LR rates were 16.9%, 23.2% and 28.5%, respectively. The 5-year cumulative LRR, EDM, LR rates were 23.2%, 26.9% and 33.3%, respectively. The 2-year iPFS, PFS and OS rates were 66.1% (95% CI: 57.9%-75.4%), 53.6% (95% CI: 45.1%-63.7%) and 80.4% (95% CI: 73.3%-88.1%), respectively. The most common grade I-Ⅱ adverse events were nausea (33.9%) and dizziness (31.3%), and only 1 patient developed grade Ⅲ nausea and dizziness. MMSE ( n=57) and HVLT-R tests ( n=56) showed no significant decline. Conclusions:Optimized HA-PCI can achieve similar dose limitation with favorable efficacy and light toxicity. No significant decline is observed in short-term neurocognitive function in evaluable patients.

6.
文章 在 中文 | WPRIM | ID: wpr-1020580

摘要

Objective:Using atenolol as a model drug,the aim of this study was to develop a sustained and controlled transdermal drug delivery system(TDDS)based on polyethyleneimine-modified MoS2 nanoparticles(PEI-MoS2 NPs)that were responsive to near infrared(NIR)laser irradiation.Methods:The three-dimensional flower-like PEI-MoS2 NPs were successfully synthesized and further characterized by attenuated total reflection Fourier transform infrared spectroscopy,X-ray diffraction measurements,scanning electron microscopy,and transmission electron microscopy.The controlled release capacity of PEI-MoS2 NPs was examined using in vitro drug release and skin penetration experiments.Results:The PEI-MoS2 NPs exhibited a drug loading efficiency of 53.86% and high photothermal conversion ability.Moreover,the release of atenolol was enhanced by NIR stimulation with an enhancement ratio of 1.56.Conclusion:NIR-controlled PEI-MoS2 NPs was essential for the control and sustained release of drugs in TDDS.

7.
文章 在 中文 | WPRIM | ID: wpr-1039048

摘要

Glioblastoma (GBM), one of the most common malignant tumors in the central nervous system (CNS), is characterized by diffuse and invasive growth as well as resistance to various combination therapies. GBM is the most prevalent type with the highest degree of malignancy and the worst prognosis. While current clinical treatments include surgical resection, radiotherapy, temozolomide chemotherapy, novel molecular targeted therapy, and immunotherapy, the median survival time of GBM patients is only about one year. Radiotherapy is one of the important treatment modalities for GBM, which relies on ionizing radiation to eradicate tumor cells. Approximately 60% to 70% of patients need to receive radiotherapy as postoperative radiotherapy or neoadjuvant radiotherapy during the treatment process. However, during radiotherapy, the radioresistant effect caused by DNA repair activation and cell apoptosis inhibition impedes the therapeutic effect of malignant glioblastoma.Ferroptosis was first proposed by Dr. Brent R. Stockwell in 2012. It is an iron-dependent mode of cell death induced by excessive lipid peroxidation. Although the application of ferroptosis in tumor therapy is still in the exploratory stage, it provides a completely new idea for tumor therapy as a novel form of cell death. Ferroptosis has played a significant role in the treatment of GBM. Specifically, research has revealed the key processes of ferroptosis occurrence, including intracellular iron accumulation, reactive oxygen species (ROS) generation, lipid peroxidation, and a decrease in the activity of the antioxidant system. Among them, glutathione peroxidase 4(GPX4) in the cytoplasm and mitochondria, ferroptosis suppressor protein 1 (FSP1) on the plasma membrane, and dihydroorotate dehydrogenase (DHODH) in the mitochondria constitute an antioxidant protection system against ferroptosis. In iron metabolism, nuclear receptor coactivator 4 (NCOA4) can mediate ferritin autophagy to regulate intracellular iron balance based on intracellular iron content. Heme oxygenase1 (HMOX1) catalyzes heme degradation to release iron and regulate ferroptosis. Radiation can trigger ferroptosis by generating ROS, inhibiting the signaling axis of the antioxidant system, depleting glutathione, upregulating acyl-CoA synthase long chain family member 4 (ACSL4), and inducing autophagy. Interestingly, some articles has documented that exposure to low doses of radiation (6 Gy for 24 h or 8 Gy for 4-12 h) can induce the expression of SLC7A11 and GPX4 in breast cancer and lung cancer cells, leading to radiation resistance, while radiation-induced ferroptosis occurs after 48 h. In contrast, high doses of ionizing radiation (20 Gy and 50 Gy) increase lipid peroxidation after 24 h. This suggests that radiation-induced oxidative stress is a double-edged sword that can regulate ferroptosis in both directions, and the ultimate fate of cells after radiation exposure——developing resistance and achieving homeostasis or undergoing ferroptosis——depends on the degree and duration of membrane lipid damage caused by the radiation dose. In addition, during the process of radiotherapy, methods such as inducing iron overload, damaging the antioxidant system, and disrupting mitochondrial function are used to target ferroptosis, thereby enhancing the radiosensitivity of glioblastoma. By promoting the occurrence of ferroptosis in tumor cells as a strategy to improve radiotherapy sensitivity, we can enhance the killing effect of ionizing radiation on tumor cells, thus providing more treatment options for patients with glioblastoma. In this paper, we reviewed ferroptosis and its mechanism, analyzed the molecular mechanism of radiation-induced ferroptosis, and discussed the effective strategies to regulate ferroptosis in enhancing the sensitivity of radiotherapy, with a view to providing an important reference value for improving the current status of glioblastoma treatment.

8.
Int. j. morphol ; 41(5): 1527-1536, oct. 2023. ilus
文章 在 英语 | LILACS | ID: biblio-1521022

摘要

SUMMARY: The 12C6+ heavy ion beam irradiation can cause bystander effects. The inflammatory cytokines, endocrine hormones and apoptotic proteins may be involved in 12C6+ irradiation-induced bystander effects. This study characterized the protective effects and mechanisms of Huangqi decoction (HQD) against 12C6+ radiation induced bystander effects. Wistar rats were randomly divided into control, 12C6+ heavy ion irradiation model, and high-dose/medium-dose/low-dose HQD groups. HE staining assessed the pathological changes of brain and kidney. Peripheral blood chemical indicators as well as inflammatory factors and endocrine hormones were detected. Apoptosis was measured with TUNEL. Proliferating cell nuclear antigen (PCNA) expression was determined with real-time PCR and Western blot.Irradiation induced pathological damage to the brain and kidney tissues. After irradiation, the numbers of white blood cells (WBC) and monocyte, and the expression of interleukin (IL)-2, corticotropin-releasing hormone (CRH) and PCNA decreased. The damage was accompanied by increased expression of IL-1β, IL-6, corticosterone (CORT) and adrenocorticotropic hormone (ACTH) as well as increased neuronal apoptosis. These effects were indicative of radiation-induced bystander effects. Administration of HQD attenuated the pathological damage to brain and kidney tissues, and increased the numbers of WBC, neutrophils, lymphocyte and monocytes, as well as the expression of IL-2, CRH and PCNA. It also decreased the expression of IL-1β, IL-6, CORT and ACTH as well as neuronal apoptosis. HQD exhibits protective effects against 12C6+ radiation-induced bystander effects. The underlying mechanism may involve the promotion of the production of peripheral blood cells, inhibition of inflammatory factors and apoptosis, and regulation of endocrine hormones.


La irradiación con haz de iones pesados 12C6+ puede provocar efectos secundarios. Las citoquinas inflamatorias, las hormonas endocrinas y las proteínas apoptóticas pueden estar involucradas en los efectos secundarios inducidos por la irradiación 12C6+. Este estudio caracterizó los efectos y mecanismos protectores de la decocción de Huangqi (HQD) contra los efectos externos inducidos por la radiación 12C6+. Las ratas Wistar se dividieron aleatoriamente en grupos control, modelo de irradiación de iones pesados 12C6+ y grupos de dosis alta/media/baja de HQD. La tinción con HE evaluó los cambios patológicos del cerebro y el riñón. Se detectaron indicadores químicos de sangre periférica, así como factores inflamatorios y hormonas endocrinas. La apoptosis se midió con TUNEL. La expresión del antígeno nuclear de células en proliferación (PCNA) se determinó mediante PCR en tiempo real y transferencia Western blot. La irradiación indujo daños patológicos en los tejidos cerebrales y renales. Después de la irradiación, disminuyó el número de glóbulos blancos (WBC) y monocitos, y la expresión de interleucina (IL)-2, hormona liberadora de corticotropina (CRH) y PCNA. El daño estuvo acompañado por una mayor expresión de IL-1β, IL-6, corticosterona (CORT) y hormona adrenocorticotrópica (ACTH), así como un aumento de la apoptosis neuronal. Estas alteraciones fueron indicativas de efectos inducidos por la radiación. La administración de HQD atenuó el daño patológico a los tejidos cerebrales y renales, y aumentó el número de leucocitos y monocitos, así como la expresión de IL-2, CRH y PCNA. También disminuyó la expresión de IL-1β, IL-6, CORT y ACTH, así como la apoptosis neuronal. HQD exhibe mecanismos protectores contra los efectos externos inducidos por la radiación 12C6+. El mecanismo subyacente puede implicar la promoción de la producción de células sanguíneas periféricas, la inhibición de factores inflamatorios y la apoptosis y la regulación de hormonas endocrinas.


Subject(s)
Animals , Female , Rats , Drugs, Chinese Herbal , Protective Agents/administration & dosage , Heavy Ions/adverse effects , Scutellaria baicalensis/chemistry , Brain/drug effects , Brain/radiation effects , Corticotropin-Releasing Hormone , Enzyme-Linked Immunosorbent Assay , Rats, Wistar , Apoptosis/drug effects , Apoptosis/radiation effects , Adrenocorticotropic Hormone , Proliferating Cell Nuclear Antigen , Endocrine System/drug effects , Endocrine System/radiation effects , Immunologic Factors/antagonists & inhibitors , Kidney/drug effects , Kidney/radiation effects
9.
International Eye Science ; (12): 551-556, 2023.
文章 在 中文 | WPRIM | ID: wpr-965775

摘要

AIM: To investigate the changes of protein expressions in human lens epithelial cells(SRA01/04)undergoing oxidative damage, hoping to provide new protein target for the pathogenesis of age-related cataract(ARC).METHODS: SRA01/04 cells were divided into experimental group and control group. In the experimental group, cells were irradiated with ultraviolet-B(UVB)for 10min to establish the model of oxidative damage, whereas cells in the control group were untreated. Protein expression profile from the two groups was sequenced by isobaric tags for relative and absolute quantitation(iTRAQ). The filtering criteria that fold change &#x0026;#x003E;1.2 and p&#x0026;#x003C;0.05 was used to determine the differentially expressed proteins(DEPs). Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)database were utilized for functional enrichment analysis of the top 50 DEPs with either up-regulated or down-regulated significance. Furthermore, Pathway commons software was used to establish the protein-protein interaction(PPI)network.RESULTS: Overall, 552 DEPs were screened out. A total of 176 DEPs were up-regulated in the experimental group compared with the control group, including HMGB1 and USP1, while 376 DEPs were down-regulated, including POLR2A and POLR2B. GO and KEGG enrichment analysis indicated that the top 50 DEPs with up-regulated or down-regulated significance were involved in various crucial biological processes and signaling pathways. PPI network revealed that oxidative damage repair(ODR)-related proteins might play a key role in UVB-induced oxidative damage.CONCLUSIONS: The expressions of multiple proteins, especially ODR-related proteins, can be altered in SRA01/04 cells via UVB irradiation. These findings may provide cellular-related insights into the pathogenesis of ARC and into proteins or pathways associated with therapeutic targets.

10.
文章 在 中文 | WPRIM | ID: wpr-973177

摘要

@#Breast cancer is the most common malignancy and the fifth leading cause of cancer-related mortality in the world. Breast cancer is a global health problem that poses a heavy burden on patients and their families as well as socioeconomic development. As an important component in the management of breast cancer, radiotherapy plays a vital role in its comprehensive treatment. This review describes advances made toward the application of adjuvant radiotherapy in the treatment of breast cancer.

11.
Acta Pharmaceutica Sinica B ; (6): 2844-2876, 2023.
文章 在 英语 | WPRIM | ID: wpr-982893

摘要

Non-invasive control of the drug molecules accessibility is a key issue in improving diagnostic and therapeutic procedures. Some studies have explored the spatiotemporal control by light as a peripheral stimulus. Phototriggered drug delivery systems (PTDDSs) have received interest in the past decade among biological researchers due to their capability the control drug release. To this end, a wide range of phototrigger molecular structures participated in the DDSs to serve additional efficiency and a high-conversion release of active fragments under light irradiation. Up to now, several categories of PTDDSs have been extended to upgrade the performance of controlled delivery of therapeutic agents based on well-known phototrigger molecular structures like o-nitrobenzyl, coumarinyl, anthracenyl, quinolinyl, o-hydroxycinnamate and hydroxyphenacyl, where either of one endows an exclusive feature and distinct mechanistic approach. This review conveys the design, photochemical properties and essential mechanism of the most important phototriggered structures for the release of single and dual (similar or different) active molecules that have the ability to quickly reason of the large variety of dynamic biological phenomena for biomedical applications like photo-regulated drug release, synergistic outcomes, real-time monitoring, and biocompatibility potential.

12.
文章 在 中文 | WPRIM | ID: wpr-1025030

摘要

Objective Using different sterilization method to sterilize pig specific formula milk powder,exploring the sterilization method and conditions that minimize the loss of nutritional components in formula milk powder.Methods Pig-specific formula milk powder was divided into high-pressure sterilization and irradiation sterilization groups.Formula milk powder in the high-pressure group was sterilized using different sterilization conditions and that in the irradiation group was sterilized using different 60 Co γ-radiation doses.The sterility and the nutritional contents of the sterilized formula milk powders were determined according to national standards.Results The sterility tests for both groups of formula milk powder were negative.Compared to control group,the crude protein contents were significantly lower in formula in the high-pressure group sterilized at 121℃for 30 min and in the irradiation liquid group sterilized at 50 kGy(P<0.01).The water,crude protein,and calcium contents were significantly lower(P<0.001)in the irradiation group sterilized at 50 kGy.There was no significant difference in the valine,isoleucine,or leucine content under 50 kGy sterilization conditions in the irradiation sterilized group,but all amino acid contents were decreased in the high-pressure sterilization and irradiation sterilized liquid groups(P<0.001).Analysis of trace elements showed an increased iron content(P<0.001)in formula sterilized at 121℃for 30 min in the high-pressure sterilization group,increased iron and potassium contents(P<0.001)under 25 kGy sterilization conditions in the irradiation sterilization liquid group,and increased magnesium content(P<0.01).The magnesium(P<0.05)and sodium contents(P<0.01)differed significantly in formula treated under 50 kGy sterilization conditions in the irradiation sterilized powder group.VE and VB2 contents were increased in formula sterilized at 121℃for 30 min in the high-pressure sterilization group(P<0.001),the VE content was increased(P<0.05)and the VB2 content was decreased(P<0.001)in formula sterilized under 50 kGy conditions in the irradiation sterilization liquid group,and the VE and VA contents were decreased in formula sterilized at 25 kGy in the irradiation sterilized powder group(P<0.001).Conclusions Sterilization at 121℃for 30 min result ed in the least loss of nutritional components in the high-pressure sterilization group,while irradiation sterilization result ed in the least loss of nutrients at a dose of 50 kGy.Comparing the two sterilization method,irradiation of milk powder at 50 kGy result ed in the least loss of nutrient content.

13.
文章 在 中文 | WPRIM | ID: wpr-1027357

摘要

Objective:To compare the radiation chemistry effects on water molecules after ultra-high dose rate (FLASH) and conventional irradiation.Methods:Both FLASH and conventional irradiation were applied to ultrapure water, with the hydroxyl radical yield in the homogeneous phase detected using electron paramagnetic resonance (EPR) and the hydrogen peroxide (H 2O 2) yield in the diffusion phase analyzed uuxing fluorescence probe. The liposome model was then established to investigate the radiation chemistry effect of FLASH and conventional irradiation in inducing lipid peroxidation. Results:Radiation chemistry reactions were observed in water molecules after irradiation. In the homogeneous phase, the yield of free radicals using FLASH irradiation is similar to those from conventional irradiation ( P>0.05). In the diffusion phase, the amount of H 2O 2 produced by FLASH irradiation was significantly lower than those from conventional irradiation ( t=0.49-12.81, P<0.05). The liposome model confirmed that conventional irradiation could significantly induce lipid peroxidation through the radiation chemistry effect in water molecules as compared with FLASH irradiation ( t=0.31-11.73, P<0.05). Conclusions:The radiation chemistry effect in water molecules after FLASH irradiation was significantly lower than that from conventional irradiation. This could be one of the mechanisms of FLASH effect.

14.
文章 在 中文 | WPRIM | ID: wpr-1027366

摘要

Objective:To evaluate the effect of long non-coding RNA PRMT5-AS1 on ferroptosis of hepatocellular carcinoma cell(HCC) after ionizing irradiation.Methods:The PRMT5-AS1 overexpression model was constructed in MHCC-97H cells and the PRMT5-AS1 knockdown model was constructed in HepG2 cells. X-ray irradiation(IR) was performed with an absorbed dose of 10 Gy and a dose rate of 3 Gy/min. Western blot and qRT-PCR were used to detect gene expression. The effect of PRMT5-AS1 expression on lipid peroxidation and ferroptosis of HCC after IR was detected by Trypan blue staining flow cytometry. The effect of PRMT5-AS1 expression on the death of HCC after IR was detected by CCK-8 assay. Dual luciferase assay to detect the binding of let-7c-5p to PRMT5-AS1 and SLC7A11.Results:Overexpression of PRMT5-AS1 in MHCC-97H cells could significantly reduce cell death induced by IR (Vector vs. PRMT5-AS1: 27.57% vs.18.30%, t=14.94, P<0.05). Knockdown of PRMT5-AS1 in HepG2 cells significantly increased cell death induced by IR (siNC vs. siPRMT5-AS1: 17.26% vs. 28.26%, t=13.63, P<0.05). Flow cytometry result show that overexpression of PRMT5-AS1 can significantly inhibit the increase of intracellular lipid ROS level induced by IR (Vector vs. PRMT5-AS1: 17.01% vs. 12.52%, t=12.80, P<0.05), and knockdown of PRMT5-AS1 significantly increases the lipid ROS level induced by IR (siNC vs. siPRMT5-AS1: 14.54% vs. 17.72%, t=5.93, P<0.05). The result of CCK-8 experiment showed that overexpression of PRMT5-AS1 could significantly inhibit Erastin induced cell activity reduction (Vector vs. PRMT5-AS1: 87.92% vs. 109.06%, t=2.87, P<0.05), and knockdown of PRMT5-AS1 could promote Erastin′s inhibitory effect on cell activity (siNC vs. siPRMT5-AS1: 82.56% vs. 60.58%, t=38.35, P<0.05). Western blot and fluorescent quantitative PCR result showed that the protein and mRNA levels of SLC7A11 were significantly increased after overexpression of PRMT5-AS1 ( t=26.24, P<0.05), and the protein and mRNA levels of SLC7A11 were significantly decreased after knockdown of PRMT5-AS1 ( t=5.60, P<0.05). The correlation between PRMT5-AS1 and let-7c-5p was confirmed by luciferase report gene experiment ( t=9.74, P<0.05). The result of luciferase reporter gene experiment showed that PRMT5-AS1 could form ceRNA network with let-7c-5p to regulate SLC7A11. Let-7c-5p was able to reverse the increase in SLC7A11 expression levels, decrease in Lipid-ROS levels and cell death induced by overexpression of PRMT5-AS1 ( t=3.01, 4.11, P<0.05). And knockdown of SLC7A11 reversed Lipid-ROS inhibition and reduced cell death caused by PRMT5-AS1( t=21.35, 7.15, P<0.05). Conclusions:LncRNA PRMT5-AS1 inhibits IR-induced ferroptosis in HCC through the PRMT5-AS1/let-7c-5p/SLC7A11 axis.

15.
文章 在 中文 | WPRIM | ID: wpr-1027370

摘要

Objective:To explore the effects of the deep inspiration breath-hold (DIBH) technique on cardiac dosimetry in internal mammary node irradiation with intensity-modulated radiation therapy (IMN-IMRT) for postoperative left breast cancer.Methods:Totally 23 left breast cancer patients in the First Affiliated Hospital of Bengbu Medical College from Octorber 2021 to July 2022 receiving postoperative IMN-IMRT were enrolled in this study. The changes in dosimetric parameters for their heart and left anterior descending coronary artery (LAD) in the DIBH mode were observed, and the potential factors affecting DIBH effects were analyzed.Results:Compared with the free breath (FB) mode, the DIBH mode manifested a heart volume decrease by 18% ( t = 10.47, P < 0.001), a left lung volume increase by 42% ( t = -14.55, P < 0.001), and significantly reduced dosimetric parameters ( Dmean, Dmax, V5- V30) for the heart and LAD, exhibiting statistically significant differences ( t=-13.38 to -3.30, P<0.05). As indicated by the Pearson correlation analysis, the relative ratio of cardiac dose reduction was positively correlated with that of left lung expansion ( r = 0.82, P < 0.001) and negatively correlated with the patient′age ( r = -0.56, P = 0.005). Conclusions:DIBH can effectively reduce the heart and LAD radiation doses in IMN-IMRT for postoperative left breast cancer and that the patient's age, and the DIBH effects might be affected by the vital capacity.

16.
文章 在 中文 | WPRIM | ID: wpr-1027428

摘要

In the era of immunotherapy, the advantages and limitations brought from elective nodal irradiation (ENI) needs to be re-evaluated. As immune organs, lymph nodes play a crucial role as barriers against cancer, and are involved in the activation of anti-tumor responses during radiotherapy. Numerous animal experiments have demonstrated a significant depletion of cytotoxic T cells in the tumor microenvironment, along with an increase in radiation resistance after ENI or surgical resection, leading to limited tumor regression. Furthermore, the abscopal effect stimulated by radiotherapy is markedly attenuated when ENI is combined with immunotherapy. In this article, research progress in the underlying mechanisms was reviewed.

17.
文章 在 中文 | WPRIM | ID: wpr-1027435

摘要

Objective:To study the relationship between endoplasmic reticulum stress (ERS) and apoptotic protein and myocardial pathological changes in rats after endostar combined with low-dose X-ray irradiation.Methods:Forty SD rats were evenly divided into four groups: control group (intraperitoneal injection of equal volume physiological saline, once per day, 14 d), endostar group (intraperitoneal injection of endostar 6 mg/kg, once per day, 14 d), irradiation group (15 Gy divided into 3 times X-ray irradiation) and combination group (intraperitoneal injection of endostar after irradiation at the same dose and time as the endostar group). At 1 and 6 months after treatment, myocardial tissues of rats were prepared for HE staining and Masson staining to observe the myocardial histological changes. TUNEL assay was used to detect myocardial cell apoptosis, and ImageJ software was utilized to calculate myocardial collagen volume fraction (CVF). The expression levels of ERS and apoptotic protein glucose-regulated protein 78 (GRP78), protein kinase-like endoplasmic reticulum kinases (PERK), CCAAT/enhancer binding protein homologous protein (CHOP) and cysteine-containing aspartate-specific protease-12 (Caspase-12) were detected by Western blot. One-way ANOVA was conducted using GraphPad Prism 8.0.1 software, and comparison between two groups was conducted using t-test. Results:At 6 months after treatment, the myocardial interstitium in the irradiation and combination groups was widened, showing strip-like or reticular fibrosis changes, and the myocardial interstitium had diffuse collagen fiber deposition. Compared with the control group, CVF was increased significantly (both P<0.01). At 1 and 6 months after treatment, the apoptotic index of myocardial cells in the combination group was significantly higher than that in the control group ( P<0.05, <0.001). At 1 and 6 months after treatment, the expression levels of GRP78 protein in the irradiation and combination groups were increased (all P<0.01), and the expression levels of PERK and CHOP proteins in the combination group were increased compared to those in the control group (both P<0.05). At 6 months after treatment, the expression levels of PERK and CHOP proteins in the irradiation group were increased compared to those in the control group (both P<0.05). Compared with the control group, Caspase-12 expression levels at 1 and 6 months after treatment were increased in the endostar, irradiation and combination groups (all P<0.05). Conclusions:The expression levels of ERS and apoptotic proteins are related to cardiac injury caused by irradiation in rats. After low-dose X-ray combined with endostar treatment, ERS is aggravated and myocardial apoptosis is increased.

18.
Tumor ; (12): 729-739, 2023.
文章 在 中文 | WPRIM | ID: wpr-1030324

摘要

Objective:This study aimed to compare the dosimetric differences in unintended irradiation to the ipsilateral axillary region between intensity-modulated radiation therapy(IMRT)and intensity-modulated proton therapy(IMPT)in patients receiving whole breast irradiation(WBI). Methods:A total of 20 patients with early breast cancer who received WBI at our center between August and September 2022 were included in this study.One IMPT plan and one IMRT plan were formulated for each patient,with prescription dose of 4005 cGy(RBE)in 1 5 fractions.Dosimetric parameters of axillary lymph nodes(ALN)level Ⅰ,Ⅱ,Ⅲ,Rotter's lymph nodes(RN),and the axillary-lateral thoracic vascular junction(ALTJ)were compared between IMPT and IMRT plans. Results:All plans met the criteria of CTV V95%Dose≥95%.IMPT showed significantly better conformity index(0.97 vs 0.95,P=0.0003)and homogeneity index(0.05 vs 0.07,P=0.0301)compared to IMRT.The mean dose of the heart[27.48 vs 114.74 cGy(RBE),P<0.0001]and ipsilateral lung[356.66 vs 498.89 cGy(RBE),P<0.0001]were significantly lower in the IMPT plan compared to the IMRT plan.The mean dose,V50%Dose,V80%Dose,V90%Dose,and V95%Dose of ALNⅠ,ALN Ⅱ,ALN Ⅲ and RN in the IMPT plan were significantly lower than those in the IMRT plan(all P<0.01),with the most significant difference observed in the dosimetric parameters of the axillary region inferior to the axillary vein[mean dose:79.75 vs 995.31 cGy(RBE),P<0.0001].The mean dose and serial dosimetric parameters(V5,V10,V15,V20,V25,V30,and V35)of the ALTJ were also significantly lower in IMPT plans compared to IMRT plans. Conclusion:IMPT demonstrates lower unintended irradiation dose in the inferior axillary region and reduces dose volume in the ALTJ region compared to IMRT.When employing IMPT,the clinical target volume(CTV)should be delineated based on the individual locoregional recurrence risk for patients with positive sentinel lymph nodes who omitted axillary lymph node dissection.For high-risk patients,the axillary region should be included in the CTV to ensure efficacy,while for low-risk patients,excluding the axillary region can help mitigate the risk of breast cancer-related lymphedema.

19.
文章 在 中文 | WPRIM | ID: wpr-1018208

摘要

Objective:To study the effects of electron beam irradiation and 60Co irradiation on the composition changes of four alkaloids in Sophorae Flavescentis Radix, intermediate extracts of Sophorae Flavescentis Radix and Lixieling Tablets. Methods:Sophorae Flavescentis Radix, intermediate extracts of Sophorae Flavescentis Radix and Lixieling Tablets were irradiated at different doses of 0, 1.5, 3, 5, 7, 10, 20, 30, 40 kGy by electron beam irradiation and 60Co irradiation. The contents of oxymatrine, oxysophocarpine, matrine and sophocarpine were determined by HPLC, and the changes of the components before and after irradiation were compared. Results:Oxymatrine, oxysophocarpine, matrine and sophocarpine were among 0.046 9-0.937 4 μg, 0.020 5-0.410 4 μg, 0.098 9-1.977 9 μg, 0.048 7-0.973 1 μg, respectively. The linear relationship was good. The average recovery rates were 98.1%, 100.1%, 100.5%, 96.6%, respectively, and the RSDs were 1.69%, 2.03%, 3.14% and 1.10%, respectively. Electron beam irradiation and 60Co irradiation had no statistical significance on the changes of oxymatrine, oxysophocarpine, matrine and sophocarpine in Sophora flavescens, but had statistical significance in the contents of intermediate extracts of Sophorae Flavescentis Radix and Lixieling Tablets. Conclusion:The established method for the determination of matrine is accurate, reproducible, simple and practical, and can be used for the quality control of Lixieling Tablets. Irradiation has no significant effect on the content of Sophorae Flavescentis Radix, while high dose irradiation has significant effect on the intermediates and finished products of Sophorae Flavescentis Radix, which can provide a basis for quality control and sterilization irradiation of enterprises.

20.
文章 在 中文 | WPRIM | ID: wpr-993068

摘要

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.

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