1.Mechanism of Naoxintong Capsules in treatment of rats with multiple cerebral infarctions and myocardial injury based on HIF-1α/VEGF pathway.
Xiao-Lu ZHANG ; Jin-Feng SHANG ; Yin-Lian WEN ; Gui-Jin-Feng HUANG ; Bo-Hong WANG ; Wan-Ting WEI ; Wen-Bin CHEN ; Xin LIU
China Journal of Chinese Materia Medica 2025;50(7):1889-1899
This study aims to explore whether Naoxintong Capsules improve multiple cerebral infarctions and myocardial injury via promoting angiogenesis, thereby exerting a simultaneous treatment effect on both the brain and heart. Male SD rats were randomly divided into six groups: sham-operated group, model group, high-dose, medium-dose, and low-dose groups of Naoxintong Capsules(440, 220, and 110 mg·kg~(-1)), and nimodipine group(10.8 mg·kg~(-1)). Rat models of multiple cerebral infarctions were established by injecting autologous thrombus, and samples were collected and tested seven days after modeling. Evaluations included multiple cerebral infarction model assessments, neurological function scores, grip strength tests, and rotarod tests, so as to evaluate neuromotor functions. Morphological structures of brain and heart tissue were observed using hematoxylin-eosin(HE) staining, Nissl staining, and Masson staining. Network pharmacology was employed to screen the mechanisms of Naoxintong Capsules in improving multiple cerebral infarctions and myocardial injury. Neuronal and myocardial cell ultrastructures were observed using transmission electron microscopy. Apoptosis rate in brain neuronal cells was detected by TdT-mediated dUTP nick end labeling(TUNEL) staining, and reactive oxygen species(ROS) levels in myocardial cells were measured. Immunofluorescence was used to detect the expression of platelet endothelial cell adhesion molecule-1(CD31), antigen identified by monoclonal antibody Ki67(Ki67), hematopoietic progenitor cell antigen CD34(CD34), and hypoxia inducible factor-1α(HIF-1α) in brain and myocardial tissue. Western blot, and real-time quantitative polymerase chain reaction(RT-qPCR) were used to detect the expression of HIF-1α, vascular endothelial growth factor(VEGF), vascular endothelial growth factor receptor 2(VEGFR2), sarcoma(Src), basic fibroblast growth factor(bFGF), angiopoietin-1(Ang-1), and TEK receptor tyrosine kinase(Tie-2). Compared with the model group, the medium-dose group of Naoxintong Capsules showed significantly lower neurological function scores, increased grip strength, and prolonged time on the rotarod. Pathological damage in brain and heart tissue was reduced, with increased and more orderly arranged mitochondria in neurons and cardiomyocytes. Apoptosis in brain neuronal cells was decreased, and ROS levels in cardiomyocytes were reduced. The microvascular density and endothelial cells of new blood vessels in brain and heart tissue increased, with increased overlapping regions of CD31 and Ki67 expression. The relative protein and mRNA expression levels of HIF-1α, VEGF, VEGFR2, Src, Ang-1, Tie-2, and bFGF were elevated in brain tissue and myocardial tissue. Naoxintong Capsules may improve multiple cerebral infarctions and myocardial injury by mediating HIF-1α/VEGF expression to promote angiogenesis.
Animals
;
Male
;
Drugs, Chinese Herbal/administration & dosage*
;
Rats, Sprague-Dawley
;
Rats
;
Cerebral Infarction/genetics*
;
Hypoxia-Inducible Factor 1, alpha Subunit/genetics*
;
Vascular Endothelial Growth Factor A/genetics*
;
Capsules
;
Signal Transduction/drug effects*
;
Humans
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Brain/metabolism*
;
Myocardium/metabolism*
;
Apoptosis/drug effects*
2.Color-component correlation and mechanism of component transformation of processed Citri Reticulatae Semen.
Kui-Lin ZHU ; Jin-Lian ZOU ; Xu-Li DENG ; Mao-Xin DENG ; Hai-Ming WANG ; Rui YIN ; Zhang-Xian CHEN ; Yun-Tao ZHANG ; Hong-Ping HE ; Fa-Wu DONG
China Journal of Chinese Materia Medica 2025;50(9):2382-2390
High-performance liquid chromatography(HPLC) was used to determine the content of three major components in Citri Reticulatae Semen(CRS), including limonin, nomilin, and obacunone. The chromaticity of the CRS sample during salt processing and stir-frying was measured using a color difference meter. Next, the relationship between the color and content of the salt-processed CRS sample was investigated through correlation analysis. By integrating the oil bath technique for processing simulation with HPLC, the changes in the relative content of nomilin and its transformation products were analyzed, with its structural transformation pattern during processing identified. Additionally, RAW264.7 cells were induced with lipopolysaccharides(LPSs) to establish an inflammatory model, and the anti-inflammatory activity of nomilin and its transformation product, namely obacunone was evaluated. The results indicated that as processing progressed, E~*ab and L~* values showed a downward trend; a~* values exhibited a slow increase over a certain period, followed by no significant changes, and b~* values remained stable with no significant changes over a certain period and then started to decrease. The limonin content remained barely unchanged; the nomilin content decreased, and the obacunone increased significantly. The changing trends in content and color parameters during salt-processing and stir-frying were basically consistent. The content of nomilin and obacunone was significantly correlated with the colorimetric values(L~*, a~*, b~*, and E~*ab), while limonin content showed no significant correlation with these values. By analyzing HPLC patterns of nomylin at different heating temperatures and time, it was found that under conditions of 200-250 ℃ for heating of 5-60 min, the content of nomilin significantly decreased, while the obacunone content increased pronouncedly. The in vitro anti-inflammatory activity results indicated that compared to the model group, the group with a high concentration of nomilin and the groups with varying concentrations of obacunone showed significantly reduced release of nitric oxide(NO)(P<0.01). When both were at the same concentration, obacunone showed better performance in inhibiting NO release. In this study, the obvious correlation between the color and content of major components during the processing of CRS samples was identified, and the dynamic patterns of quality change in CRS samples during processing were revealed. Additionally, the study revealed and confirmed the transformation of nomilin into obacunone during processing, with the in vitro anti-inflammatory activity of obacunone significantly greater than that of nomilin. These findings provided a scientific basis for CRS processing optimization, tablet quality control, and its clinical application.
Mice
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Animals
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Drugs, Chinese Herbal/pharmacology*
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RAW 264.7 Cells
;
Limonins/chemistry*
;
Chromatography, High Pressure Liquid
;
Citrus/chemistry*
;
Color
;
Benzoxepins/chemistry*
;
Anti-Inflammatory Agents/chemistry*
3.Mechanism related to bile acids metabolism of liver injury induced by long-term administration of emodin.
Jing-Zhuo TIAN ; Lian-Mei WANG ; Yan YI ; Zhong XIAN ; Nuo DENG ; Yong ZHAO ; Chun-Ying LI ; Yu-Shi ZHANG ; Su-Yan LIU ; Jia-Yin HAN ; Chen PAN ; Chen-Yue LIU ; Jing MENG ; Ai-Hua LIANG
China Journal of Chinese Materia Medica 2025;50(11):3079-3087
Emodin is a hydroxyanthraquinone compound that is widely distributed and has multiple pharmacological activities, including anti-diarrheal, anti-inflammatory, and liver-protective effects. Research indicates that emodin may be one of the main components responsible for inducing hepatotoxicity. However, studies on the mechanisms of liver injury are relatively limited, particularly those related to bile acids(BAs) metabolism. This study aims to systematically investigate the effects of different dosages of emodin on BAs metabolism, providing a basis for the safe clinical use of traditional Chinese medicine(TCM)containing emodin. First, this study evaluated the safety of repeated administration of different dosages of emodin over a 5-week period, with a particular focus on its impact on the liver. Next, the composition and content of BAs in serum and liver were analyzed. Subsequently, qRT-PCR was used to detect the mRNA expression of nuclear receptors and transporters related to BAs metabolism. The results showed that 1 g·kg~(-1) emodin induced hepatic damage, with bile duct hyperplasia as the primary pathological manifestation. It significantly increased the levels of various BAs in the serum and primary BAs(including taurine-conjugated and free BAs) in the liver. Additionally, it downregulated the mRNA expression of farnesoid X receptor(FXR), retinoid X receptor(RXR), and sodium taurocholate cotransporting polypeptide(NTCP), and upregulated the mRNA expression of cholesterol 7α-hydroxylase(CYP7A1) in the liver. Although 0.01 g·kg~(-1) and 0.03 g·kg~(-1) emodin did not induce obvious liver injury, they significantly increased the level of taurine-conjugated BAs in the liver, suggesting a potential interference with BAs homeostasis. In conclusion, 1 g·kg~(-1) emodin may promote the production of primary BAs in the liver by affecting the FXR-RXR-CYP7A1 pathway, inhibit NTCP expression, and reduce BA reabsorption in the liver, resulting in BA accumulation in the peripheral blood. This disruption of BA homeostasis leads to liver injury. Even doses of emodin close to the clinical dose can also have a certain effect on the homeostasis of BAs. Therefore, when using traditional Chinese medicine or formulas containing emodin in clinical practice, it is necessary to regularly monitor liver function indicators and closely monitor the risk of drug-induced liver injury.
Emodin/administration & dosage*
;
Bile Acids and Salts/metabolism*
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Animals
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Male
;
Liver/injuries*
;
Chemical and Drug Induced Liver Injury/genetics*
;
Drugs, Chinese Herbal/adverse effects*
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Humans
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Rats, Sprague-Dawley
;
Mice
;
Rats
4.RXRα modulates hepatic stellate cell activation and liver fibrosis by targeting CaMKKβ-AMPKα axis.
Lijun CAI ; Meimei YIN ; Shuangzhou PENG ; Fen LIN ; Liangliang LAI ; Xindao ZHANG ; Lei XIE ; Chuanying WANG ; Huiying ZHOU ; Yunfeng ZHAN ; Gulimiran ALITONGBIEKE ; Baohuan LIAN ; Zhibin SU ; Tenghui LIU ; Yuqi ZHOU ; Zongxi LI ; Xiaohui CHEN ; Qi ZHAO ; Ting DENG ; Lulu CHEN ; Jingwei SU ; Luoyan SHENG ; Ying SU ; Ling-Juan ZHANG ; Fu-Quan JIANG ; Xiao-Kun ZHANG
Acta Pharmaceutica Sinica B 2025;15(7):3611-3631
Hepatic stellate cells (HSCs) are the primary fibrogenic cells in the liver, and their activation plays a crucial role in the development and progression of hepatic fibrosis. Here, we report that retinoid X receptor-alpha (RXRα), a unique member of the nuclear receptor superfamily, is a key modulator of HSC activation and liver fibrosis. RXRα exerts its effects by modulating calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ)-mediated activation of AMP-activated protein kinase-alpha (AMPKα). In addition, we demonstrate that K-80003, which binds RXRα by a unique mechanism, effectively suppresses HSC activation, proliferation, and migration, thereby inhibiting liver fibrosis in the CCl4 and amylin liver NASH (AMLN) diet animal models. The effect is mediated by AMPKα activation, promoting mitophagy in HSCs. Mechanistically, K-80003 activates AMPKα by inducing RXRα to form condensates with CaMKKβ and AMPKα via a two-phase process. The formation of RXRα condensates is driven by its N-terminal intrinsic disorder region and requires phosphorylation by CaMKKβ. Our results reveal a crucial role of RXRα in liver fibrosis regulation through modulating mitochondrial activities in HSCs. Furthermore, they suggest that K-80003 and related RXRα modulators hold promise as therapeutic agents for fibrosis-related diseases.
5.Multicenter study on the detection of pathogens in primary infectious diseases of the spine using metagenomic next-generation sequencing technology
Zhaohui LI ; Qiang ZHANG ; Huafeng WANG ; Tengbo YU ; Yuelei WANG ; Jinlong MA ; Chuqiang YIN ; Feng SHEN ; Yidan XU ; Xiaofeng LIAN ; Ting WANG
Chinese Journal of Surgery 2024;62(12):1128-1135
Objective:To explore the role of metagenomic next-generation sequencing (mNGS) in the diagnosis of pathogens in primary infectious diseases of the spine (IDS) and to reveal its pathogen spectrum.Methods:This is a retrospective multi-center case series study. Clinical data of 380 patients with primary IDS who were treated at four medical centers in China from December 2019 to April 2024 were retrospectively analyzed. Among them, 82 cases were from the Department of Spine Surgery at the Affiliated Hospital of Qingdao University, 129 cases were from the Orthopedics Section Ⅱ (Bone Infection), Public Health Clinical Center Affiliated to Shandong University, 112 cases were from the Department of Spine Surgery, Fuzhou Second General Hospital, and 57 cases were from the Department of Orthopedic Surgery, Shanghai Sixth People′s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. There were 238 males and 242 females, with an age of (61.4±13.1) years (range: 10 to 91 years). Specimens from the site of spinal infection were obtained for pathogen culture, pathological examination, and mNGS detection preoperatively or intraoperatively in all patients. The number, types, and positive rates of pathogens detected by the two methods were analyzed and compared using the Chi-square test.Results:Among the 380 patients, 320 had confirmed pathogenic bacteria, with the highest proportion being pyogenic bacterial infections, accounting for 76.9% (246/320). The most common pathogen was Staphylococcus aureus, accounting for 22.8% (73/320). Brucella accounted for 13.8% (44/320); Mycobacterium tuberculosis accounted for 6.3% (20/320). Fungal infections accounted for 3.4% (11/320), mainly Aspergillus and Candida. In addition, Mycoplasma was detected in 3 cases (0.9%) and Benacox body in 4 cases (1.2%). The pathogen spectrum constructed by mNGS covered 46 types of pathogens, higher than the 22 types detected by traditional methods. The positive rate of mNGS was 80.8% (308/381), significantly higher than the 27.9% (106/381) of traditional methods ( χ2=182.53, P<0.01). Conclusions:mNGS improves the positive rate of pathogen diagnosis in IDS, detecting a broader spectrum of pathogens, and serves as a valuable complement to traditional diagnostic methods. Combining both methods in the diagnosis of IDS can maximize detection rates, providing robust evidence for precise anti-infective treatment.
6.Multicenter study on the detection of pathogens in primary infectious diseases of the spine using metagenomic next-generation sequencing technology
Zhaohui LI ; Qiang ZHANG ; Huafeng WANG ; Tengbo YU ; Yuelei WANG ; Jinlong MA ; Chuqiang YIN ; Feng SHEN ; Yidan XU ; Xiaofeng LIAN ; Ting WANG
Chinese Journal of Surgery 2024;62(12):1128-1135
Objective:To explore the role of metagenomic next-generation sequencing (mNGS) in the diagnosis of pathogens in primary infectious diseases of the spine (IDS) and to reveal its pathogen spectrum.Methods:This is a retrospective multi-center case series study. Clinical data of 380 patients with primary IDS who were treated at four medical centers in China from December 2019 to April 2024 were retrospectively analyzed. Among them, 82 cases were from the Department of Spine Surgery at the Affiliated Hospital of Qingdao University, 129 cases were from the Orthopedics Section Ⅱ (Bone Infection), Public Health Clinical Center Affiliated to Shandong University, 112 cases were from the Department of Spine Surgery, Fuzhou Second General Hospital, and 57 cases were from the Department of Orthopedic Surgery, Shanghai Sixth People′s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. There were 238 males and 242 females, with an age of (61.4±13.1) years (range: 10 to 91 years). Specimens from the site of spinal infection were obtained for pathogen culture, pathological examination, and mNGS detection preoperatively or intraoperatively in all patients. The number, types, and positive rates of pathogens detected by the two methods were analyzed and compared using the Chi-square test.Results:Among the 380 patients, 320 had confirmed pathogenic bacteria, with the highest proportion being pyogenic bacterial infections, accounting for 76.9% (246/320). The most common pathogen was Staphylococcus aureus, accounting for 22.8% (73/320). Brucella accounted for 13.8% (44/320); Mycobacterium tuberculosis accounted for 6.3% (20/320). Fungal infections accounted for 3.4% (11/320), mainly Aspergillus and Candida. In addition, Mycoplasma was detected in 3 cases (0.9%) and Benacox body in 4 cases (1.2%). The pathogen spectrum constructed by mNGS covered 46 types of pathogens, higher than the 22 types detected by traditional methods. The positive rate of mNGS was 80.8% (308/381), significantly higher than the 27.9% (106/381) of traditional methods ( χ2=182.53, P<0.01). Conclusions:mNGS improves the positive rate of pathogen diagnosis in IDS, detecting a broader spectrum of pathogens, and serves as a valuable complement to traditional diagnostic methods. Combining both methods in the diagnosis of IDS can maximize detection rates, providing robust evidence for precise anti-infective treatment.
7.Efficacy of cosmetic suturing techniques combined with topical recombinant human basic fibroblast growth factor in repairing facial trauma
Huibin LIAN ; Pingsong LI ; Kunjie RONG ; Gang XU ; Jie ZHOU ; Yi LUO ; Zhongyin ZHUFU ; Haibin JU ; Junjun JIN ; Rui JIAO ; Xiaowei ZHANG ; Zhimin YIN
Chinese Journal of Medical Aesthetics and Cosmetology 2024;30(6):571-575
Objective:To observe the efficacy of cosmetic suturing techniques combined with topical recombinant human basic fibroblast growth factor (rh-bFGF) in repairing facial trauma.Methods:A prospective study was conducted on 140 patients with facial trauma admitted to the Department of Burn and Plastic Surgery, Northern Jiangsu People's Hospital from January to December 2022. Patients were divided into two groups based on different treatment methods using a random number table method: treatment group (70 cases), including 38 males and 32 females aged 3 to 54 (23.1±8.2) years, received cosmetic suturing techniques combined with topical rh-bFGF for wound repair; control group (70 cases), including 36 males and 34 females aged 2 to 49 (22.3±7.5) years, only received cosmetic suturing techniques for wound repair. Patients were followed up 2 weeks post-surgery to evaluate wound healing quality. Patient satisfaction was assessed using the visual analogue scale (VAS). Six months post-surgery, scar conditions were evaluated using the Vancouver scar scale (VSS).Results:In the treatment group, 65 cases were directly sutured, and 5 cases were repaired with skin flaps, with a first-class healing rate of 100% (70/70). In the control group, 66 cases were directly sutured, and 4 cases were repaired with skin flaps, with a first-class healing rate of 91.4% (64/70). The first-class healing rate in the treatment group was higher than that in the control group, with a statistically significant difference ( P=0.037). Two weeks post-surgery, the VAS score for surgical satisfaction in the treatment group was (1.13±0.52) scores, which was lower than that in the control group (2.56±1.32) scores, with a statistically significant difference ( P<0.001). Six months post-surgery, the VSS score for the treatment group was (2.49±1.27) scores, which was lower than that in the control group (4.67±1.93) scores, with a statistically significant difference ( P<0.001). Conclusions:In repairing facial trauma, the combination of cosmetic suturing techniques and topical rh-bFGF can improve wound healing quality, reduce wound scarring, and enhance patient satisfaction with surgery.
8.Construction and stability analysis of finite element model for spinal canal reconstruction with miniplates fixation
Jian-Min CHEN ; Guo-Yin LIU ; Wei-Qian HUANG ; Zhong-Hua LIAN ; Er-Lai ZHANG ; Jian-Ning ZHAO
China Journal of Orthopaedics and Traumatology 2024;37(3):271-277
Objective To establish the finite element model of spinal canal reconstruction and internal fixation,analysis influence of spinal canal reconstruction and internal fixation on spinal stability,and verify the effectiveness and reliability of spinal canal reconstruction and internal fixation in spinal canal surgery.Methods A 30-year-old male healthy volunteer with a height of 172 cm and weight of 75 kg was selected and his lumbar CT data were collected to establish a finite element model of normal lumbar Lo3-L,and the results were compared with in vitro solid results and published finite element analysis results to verify the validity of the model.They were divided into normal group,laminectomy group and spinal canal reconstruction group according to different treatment methods.Under the same boundary fixation and physiological load conditions,six kinds of ac-tivities were performed,including forward bending,backward extension,left bending,right bending,left rotation and right rota-tion,and the changes of range of motion(ROM)of L3-L4,L4-L5 segments and overall maximum ROM of L3-L5 were analyzed under the six conditions.Results The ROM displacement range of each segment of the constructed L3-L5 finite element model was consistent with the in vitro solid results and previous literature data,which confirms the validity of the model.In L3-L4,ROM of spinal canal reconstruction group was slightly increased than that of normal group during posterior extension(>5%dif-ference),and ROM of other conditions was similar to that of normal group(<5%difference).ROM in laminectomy group was significantly increase than that in normal group and spinal canal reconstruction group under the condition of flexion,extension,left and right rotation.In L4-L5,ROM in spinal canal reconstruction group was similar to that in normal group(<5%differ-ence),while ROM in laminectomy group was significantly higher than that in normal group and spinal canal reconstruction group(>5%difference).In the overall maximum ROM of L3-L5,spinal canal reconstruction group was only slightly higher than normal group under the condition of posterior extension(>5%difference),while laminectomy was significantly higher than normal group and spinal canal reconstruction group under the condition of anterior flexion,posterior extension,left and right rotation(>5%difference).The changes of each segment ROM and overall ROM of L3-L5 showed laminectomy group>spinal canal reconstruction group>normal group.Conclusion Laminectomy could seriously affect biomechanical stability of the spine,but application of spinal canal reconstruction and internal fixation could effectively reduce ROM displacement of the responsi-ble segment of spine and maintain its biomechanical stability.
9.Chrysin alleviates cerebral ischemia-reperfusion injury by inhibiting ferroptosis in rats.
Jin-Feng SHANG ; Jia-Kang JIAO ; Qian-Nan LI ; Ying-Hui LU ; Jing-Yi WANG ; Ming-Xue YAN ; Yin-Lian WEN ; Gui-Jin-Feng HUANG ; Xiao-Lu ZHANG ; Xin LIU
China Journal of Chinese Materia Medica 2023;48(6):1597-1605
The purpose of this study is to investigate whether chrysin reduces cerebral ischemia-reperfusion injury(CIRI) by inhi-biting ferroptosis in rats. Male SD rats were randomly divided into a sham group, a model group, high-, medium-, and low-dose chrysin groups(200, 100, and 50 mg·kg~(-1)), and a positive drug group(Ginaton, 21.6 mg·kg~(-1)). The CIRI model was induced in rats by transient middle cerebral artery occlusion(tMCAO). The indexes were evaluated and the samples were taken 24 h after the operation. The neurological deficit score was used to detect neurological function. The 2,3,5-triphenyl tetrazolium chloride(TTC) staining was used to detect the cerebral infarction area. Hematoxylin-eosin(HE) staining and Nissl staining were used to observe the morphological structure of brain tissues. Prussian blue staining was used to observe the iron accumulation in the brain. Total iron, lipid pero-xide, and malondialdehyde in serum and brain tissues were detected by biochemical reagents. Real-time quantitative polymerase chain reaction(RT-qPCR), immunohistochemistry, and Western blot were used to detect mRNA and protein expression of solute carrier fa-mily 7 member 11(SLC7A11), transferrin receptor 1(TFR1), glutathione peroxidase 4(GPX4), acyl-CoA synthetase long chain family member 4(ACSL4), and prostaglandin-endoperoxide synthase 2(PTGS2) in brain tissues. Compared with the model group, the groups with drug intervention showed restored neurological function, decreased cerebral infarction rate, and alleviated pathological changes. The low-dose chrysin group was selected as the optimal dosing group. Compared with the model group, the chrysin groups showed reduced content of total iron, lipid peroxide, and malondialdehyde in brain tissues and serum, increased mRNA and protein expression levels of SLC7A11 and GPX4, and decreased mRNA and protein expression levels of TFR1, PTGS2, and ACSL4. Chrysin may regulate iron metabolism via regulating the related targets of ferroptosis and inhibit neuronal ferroptosis induced by CIRI.
Rats
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Male
;
Animals
;
Rats, Sprague-Dawley
;
Ferroptosis
;
Signal Transduction
;
Brain Ischemia/metabolism*
;
Cyclooxygenase 2/metabolism*
;
RNA, Messenger
;
Cerebral Infarction
;
Reperfusion Injury/metabolism*
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Malondialdehyde
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Infarction, Middle Cerebral Artery
10.Study on the sensitivity of a volumetric modulated arc therapy plan verification equipment on multi-leaf collimator opening and closing errors and its gamma pass rate limit.
Jinyou HU ; Lian ZOU ; Shaoxian GU ; Ningyu WANG ; Fengjie CUI ; Shengyuan ZHANG ; Chu'ou YIN ; Yunzhu CAI ; Chengjun GOU ; Zhangwen WU
Journal of Biomedical Engineering 2023;40(1):133-140
To investigate the γ pass rate limit of plan verification equipment for volumetric modulated arc therapy (VMAT) plan verification and its sensitivity on the opening and closing errors of multi-leaf collimator (MLC), 50 cases of nasopharyngeal carcinoma VMAT plan with clockwise and counterclockwise full arcs were randomly selected. Eight kinds of MLC opening and closing errors were introduced in 10 cases of them, and 80 plans with errors were generated. Firstly, the plan verification was conducted in the form of field-by-field measurement and true composite measurement. The γ analysis with the criteria of 3% dose difference, distance to agreement of 2 mm, 10% dose threshold, and absolute dose global normalized conditions were performed for these fields. Then gradient analysis was used to investigate the sensitivity of field-by-field measurement and true composite measurement on MLC opening and closing errors, and the receiver operating characteristic curve (ROC) was used to investigate the optimal threshold of γ pass rate for identifying errors. Tolerance limits and action limits for γ pass rates were calculated using statistical process control (SPC) method for another 40 cases. The error identification ability using the tolerance limit calculated by SPC method and the universal tolerance limit (95%) were compared with using the optimal threshold of ROC. The results show that for the true composite measurement, the clockwise arc and the counterclockwise arc, the descent gradients of the γ passing rate with per millimeter MLC opening error are 10.61%, 7.62% and 6.66%, respectively, and the descent gradients with per millimeter MLC closing error are 9.75%, 7.36% and 6.37%, respectively. The optimal thresholds obtained by the ROC method are 99.35%, 97.95% and 98.25%, respectively, and the tolerance limits obtained by the SPC method are 98.98%, 97.74% and 98.62%, respectively. The tolerance limit calculated by SPC method is close to the optimal threshold of ROC, both of which could identify all errors of ±2 mm, while the universal tolerance limit can only partially identify them, indicating that the universal tolerance limit is not sensitive on some large errors. Therefore, considering the factors such as ease of use and accuracy, it is suggested to use the true composite measurement in clinical practice, and to formulate tolerance limits and action limits suitable for the actual process of the institution based on the SPC method. In conclusion, it is expected that the results of this study can provide some references for institutions to optimize the radiotherapy plan verification process, set appropriate pass rate limit, and promote the standardization of plan verification.
Humans
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Radiotherapy, Intensity-Modulated
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Immune Tolerance
;
Nasopharyngeal Carcinoma
;
ROC Curve
;
Nasopharyngeal Neoplasms/radiotherapy*

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