Objective To investigate the changes in eosinophil counts and the activation of microglial cells in the brain tissues of mice at different stages of Angiostrongylus cantonensis infection, and to examine the role of microglia in regulating the progression of angiostrongyliasis and unravel the possible molecular mechanisms. Methods Fifty BALB/c mice were randomly divided into the control group and the 7-d, 14-d, 21-day and 25-d infection groups, of 10 mice in each group. All mice in infection groups were infected with 30 stage III A. cantonensis larvae by gavage, and animals in the control group was given an equal amount of physiological saline. Five mice were collected from each of infection groups on days 7, 14, 21 d and 25 d post-infection, and 5 mice were collected from the control group on the day of oral gavage. The general and focal functional impairment was scored using the Clark scoring method to assess the degree of mouse neurological impairment. Five mice from each of infection groups were sacrificed on days 7, 14, 21 d and 25 d post-infection, and 5 mice from the control group were sacrificed on the day of oral gavage. Mouse brain tissues were sampled, and the pathological changes of brain tissues were dynamically observed using hematoxylin and eosin (HE) staining. Immunofluorescence staining with eosinophilic cationic protein (ECP) and ionized calcium binding adaptor molecule 1 (Iba1) was used to assess the degree of eosinophil infiltration and the counts of microglial cells in mouse brain tissues in each group, and the morphological parameters of microglial cells (skeleton analysis and fractal analysis) were quantified by using Image J software to determine the morphological changes of microglial cells. In addition, the expression of M1 microglia markers Fcγ receptor III (Fcgr3), Fcγ receptor IIb (Fcgr2b) and CD86 antigen (Cd86), M2 microglia markers Arginase 1 (Arg1), macrophage mannose receptor C-type 1 (Mrc1), chitinase-like 3 (Chil3), and phagocytosis genes myeloid cell triggering receptor expressed on myeloid cells 2 (Trem2), CD68 antigen (Cd68), and apolipoprotein E (Apoe) was quantified using real-time quantitative reverse transcription PCR (RT-qPCR) assay in the mouse cerebral cortex of mice post-infection. Results A large number of A. cantonensis larvae were seen on the mouse meninges surface post-infection, and many neuronal nuclei were crumpled and deeply stained, with a large number of bleeding points in the meninges. The median Clark scores of mouse general functional impairment were 0 (interquartile range, 0), 0 (interquartile range, 0.5), 6 (interquartile range, 1.0), 14 (interquartile range, 8.5) points and 20 (interquartile range, 9.0) points in the control group and the 7-d, 14-d, 21-d and 25-d groups, respectively (H = 22.45, P < 0.01), and the median Clark scores of mouse focal functional impairment were 0 (interquartile range, 0), 2 (interquartile range, 2.5), 7 (interquartile range, 3.0), 18 (interquartile range, 5.0) points and 25 (interquartile range, 6.5) points in the control group and the 7-d, 14-d, 21-d and 25-d groups, respectively (H = 22.72, P < 0.01). The mean scores of mice general and focal functional impairment were all higher in the infection groups than in the control group (all P values < 0.05). Immunofluorescence staining showed a significant difference in the eosinophil counts in mouse brain tissues among the five groups (F = 40.05, P < 0.000 1), and the eosinophil counts were significantly higher in mouse brain tissues in the 14-d (3.08 ± 0.78) and 21-d infection groups (5.97 ± 1.37) than in the control group (1.00 ± 0.28) (both P values < 0.05). Semi-quantitative analysis of microglia immunofluorescence showed a significant difference in the counts of microglial cells among the five groups (F = 17.66, P < 0.000 1), and higher Iba1 levels were detected in mouse brain tissues in 14-d (5.75 ± 1.28), 21-d (6.23 ± 1.89) and 25-d infection groups (3.70 ± 1.30) than in the control group (1.00 ± 0.30) (all P values < 0.05). Skeleton and fractal analyses showed that the branch length [(162.04 ± 34.10) μm vs. (395.37 ± 64.11) μm; t = 5.566, P < 0.05] and fractal dimension of microglial cells (1.30 ± 0.01 vs. 1.41 ± 0.03; t = 5.266, P < 0.05) were reduced in mouse brain tissues in the 21-d infection group relative to the control group. In addition, there were significant differences among the 5 groups in terms of M1 and M2 microglia markers Fcgr3 (F = 48.34, P < 0.05), Fcgr2b (F = 55.46, P < 0.05), Cd86 (F = 24.44, P < 0.05), Arg1 (F = 31.18, P < 0.05), Mrc1 (F = 15.42, P < 0.05) and Chil3 (F = 24.41, P < 0.05), as well as phagocytosis markers Trem2 (F = 21.19, P < 0.05), Cd68 (F = 43.95, P < 0.05) and Apoe (F = 7.12, P < 0.05) in mice brain tissues. Conclusions A. cantonensis infections may induce severe pathological injuries in mouse brain tissues that are characterized by massive eosinophil infiltration and persistent activation of microglia cells, thereby resulting in progressive deterioration of neurological functions.

Rice is the world's largest food crop, and its yield and quality are directly related to food security and human health. Grain size, as one of the important factors determining the rice yield, has been widely concerned by breeders and researchers for a long time. To decipher the regulatory mechanism of rice grain size, we obtained a multi-tiller, dwarf, and small-grain mutant htd1 by ethyl methanesulfonate (EMS) mutation from the Japonica rice cultivar 'Zhonghua 11' ('ZH11'). Genetic analysis indicated that the phenotype of htd1 was controlled by a single recessive gene. Using the mutation site map (Mutmap) method, we identified the candidate gene OsHTD1, which encoded a carotenoid cleavage dioxygenase involved in the biosynthesis of strigolactone (SL). The SL content in htd1 was significantly lower than that in 'ZH11'. Cytological analysis showed that the grain size of the mutant decreased due to the reductions in the length and width of glume cells. The function of htd1 was further verified by the CRISPR/cas9 gene editing technology. The plants with the gene knockout exhibited similar grain size to the mutant. In addition, gene expression analysis showed that the expression levels of multiple grain size-related genes in the mutant changed significantly, suggesting that HTD1 may interact with other genes regulating grain size. This study provides a new theoretical basis for research on the regulatory mechanism of rice grain size and potential genetic resources for breeding the rice cultivars with high yields.
Oryza/growth & development* ; Mutation ; Edible Grain/growth & development* ; Alleles ; Plant Proteins/genetics* ; Dioxygenases/genetics* ; Lactones/metabolism* ; Gene Expression Regulation, Plant ; Genes, Plant ; Gene Editing ; CRISPR-Cas Systems ; Phenotype

Objective To investigate the capillarization of liver sinusoidal endothelial cells (LSECs) and its association with hepatic fibrosis during the development of alveolar echinococcosis, so as to provide the basis for unraveling the mechanisms underlying the role of LSEC in the development and prognosis of hepatic injuries and hepatic fibrosis caused by alveolar echinococcosis. Methods Forty C57BL/6 mice at ages of 6 to 8 weeks were randomly divided into a control group and 1-, 2- and 4-week infection groups, of 10 mice in each group. Each mouse in the infection groups was intraperitoneally injected with 2 000 Echinococcus multilocularis protoscoleces, while each mouse in the control group was given an equal volume of phosphate-buffered saline using the same method. All mice were sacrificed 1, 2 and 4 weeks post-infection and mouse livers were collected. The pathological changes of livers were observed using hematoxylin-eosin (HE) staining, and hepatic fibrosis was evaluated through semi-quantitative analysis of Masson’s trichrome staining-positive areas. The activation of hepatic stellate cells (HSCs) and extracellular matrix (ECM) deposition were examined using immunohistochemical staining of α-smooth muscle actin (α-SMA) and collagen type I alpha 1 (COL1A1), and the fenestrations on the surface of LSECs were observed using scanning electron microscopy. Primary LSECs were isolated from mouse livers, and the mRNA expression of LSEC marker genes Stabilin-1, Stabilin-2, Ehd3, CD209b, GATA4 and Maf was quantified using real-time fluorescence quantitative PCR (qPCR) assay. Results Destruction of local liver lobular structure was observed in mice 2 weeks post-infection with E. multilocularis protoscoleces, and hydatid cysts, which were surrounded by granulomatous tissues, were found in mouse livers 4 weeks post-infection. Semi-quantitative analysis of Masson’s trichrome staining showed a significant difference in the proportion of collagen fiber contents in mouse livers among the four groups (F = 26.060, P < 0.001), and a higher proportion of collagen fiber contents was detected in mouse livers in the 4-week infection group [(11.29 ± 2.58)%] than in the control group (P < 0.001). Immunohistochemical staining revealed activation of a few HSCs and ECM deposition in mouse livers 1 and 2 weeks post-infection, and abundant brown-yellow stained α-SMA and COL1A1 were deposited in the lesion areas in mouse livers 4 weeks post-infection, which spread to surrounding tissues. Semi-quantitative analysis revealed significant differences in α-SMA (F = 7.667, P < 0.05) and COL1A1 expression (F = 6.530, P < 0.05) in mouse levers among the four groups, with higher α-SMA [(7.13 ± 3.68)%] and COL1A1 expression [(13.18 ± 7.20)%] quantified in mouse livers in the 4-week infection group than in the control group (both P values < 0.05). Scanning electron microscopy revealed significant differences in the fenestration frequency (F = 37.730, P < 0.001) and porosity (F = 16.010, P < 0.001) on the surface of mouse LSECs among the four groups, and reduced fenestration frequency and porosity were observed in the 1-[(1.22 ± 0.48)/μm² and [(3.05 ± 0.91)%] and 2-week infection groups [(3.47 ± 0.10)/μm² and (7.57 ± 0.23)%] groups than in the control group (all P values < 0.001). There was a significant difference in the average fenestration diameter on the surface of mouse LSECs among the four groups (F = 15.330, P < 0.001), and larger average fenestration diameters were measured in the 1-[(180.80 ± 16.42) nm] and 2-week infection groups [(161.70 ± 3.85) nm] than in the control group (both P values < 0.05). In addition, there were significant differences among the four groups in terms of Stabilin-1 (F = 153.100, P < 0.001), Stabilin-2 (F = 57.010, P < 0.001), Ehd3 (F = 31.700, P < 0.001), CD209b (F = 177.400, P < 0.001), GATA4 (F = 17.740, P < 0.001), and Maf mRNA expression (F = 72.710, P < 0.001), and reduced mRNA expression of Stabilin-1, Stabilin-2, Ehd3, CD209b, GATA4 and Maf genes was quantified in three infection groups than in the control group (all P values < 0.001). Conclusions E. multilocularis infections may induce capillarization of LSECs in mice, and result in a reduction in the expression of functional and phenotypic marker genes of LSECs, and capillarization of LSECs occurs earlier than activation of HSC and development of hepatic fibrosis.

BACKGROUND:The Yi people have used Sambucus adnata Wall to treat fractures,bruises,arthritis,etc.The author's group found that the active site aqueous extract(SAW-A)and dichloromethane extract(SAW-B)can promote fracture healing by promoting the expression of genes related to osteoblast proliferation,differentiation and maturation,differentiation and maturation.However,the therapeutic effect of methanol extract(SAW-C)at its active site on osteoarthritis is unclear. OBJECTIVE:To investigate the therapeutic effect of Sambucus adnata Wall extract on osteoarthritis,and to identify the effective targets of Sambucus adnata Wall extract in the treatment of osteoarthritis by network pharmacology technology. METHODS:A rat osteoarthritis model was replicated by anterior cruciate ligamentectomy and model rats were then treated with methanol extract of Sambucus adnata Wall by gavage for 21 days.On the 21st day after modeling,the knee joint of rats was detected by X-ray,the width of the knee joint was measured,oxidative stress indexes and inflammatory factors levels in serum and joint lavage fluid were detected,the morphology of the knee joint was observed by hematoxylin-eosin staining,full-thickness cartilage and hyaline cartilage thickness were measured,and the content of articular cartilage proteoglycan was observed by safranin O-fast green staining.The"drug-component-disease-target"network was constructed.Gene ontology enrichment analysis and Kyoto encyclopedia of genes and genomes enrichment analysis of effective targets were performed,and protein-protein interaction network maps were constructed using cytoscape software. RESULTS AND CONCLUSION:Sambucus adnata Wall extract could reduce tumor necrosis factor-α level in joint lavage fluid and serum levels of prostaglandin E2 and malondialdehyde,while increase the level of superoxide dismutase;relieve joint swelling caused by osteoarthritis;improve the histopathological state of articular cartilage,maintain the thickness of full-thickness articular cartilage,hyaline cartilage and the area of bone trabeculae in subchondral bone;and effectively prevent the loss of proteoglycans in articular cartilage and have a chondroprotective effect.Network pharmacological results showed that the methanol extract of Sambucus adnata Wall may have some targets related to inhibition of tumor necrosis factor,AKT1,interleukin-6,MAPK3,and SRC as well as inhibition of over-activation of EGFR signaling pathway and AGE-RAGE signaling pathway.

BACKGROUND:Previous studies showed that extracts of Sambucus adnata Wall.have the ability to promote the proliferation and differentiation of osteoblasts,fracture healing,anti-inflammatory and antioxidant effects,which can effectively alleviate the development of osteoarthritis.Vascular endothelial growth factor,on the other hand,is a biomarker for the evaluation of osteoarthritis severity. OBJECTIVE:To investigate the effect and mechanism of two extracts of Sambucus adnata Wall.(methanol extract SAW-ME and dichloromethane extract SAW-DCE)on angiogenesis in osteoarthritis. METHODS:(1)Rat models of osteoarthritis were established using anterior cruciate ligament transection and given SAW-ME and SAW-DCE.A sham group was set as a control.Immunohistochemistry and immunofluorescence were used to detect the changes of articular vascular endothelial growth factor A in joint tissue and vascular endothelial growth factor and"H"type blood vessels in serum of osteoarthritis rats.(2)Vascular endothelial cells EA.hy926 were used as the research object and intervened with SAW-ME and SAW-DCE.Cell proliferation was then detected by MTT assay.Vascular endothelial growth factor was used to induce EA.hy926 cells,and the model of angiogenesis was replicated.Cell scratch assay and tube formation assay were performed to study the role and mechanism.(3)EA.hy926 cells were used for transcriptome sequencing to analyze the characteristic changes of cell differential genes and related functions after SAW-DCE intervention. RESULTS AND CONCLUSION:(1)SAW-ME and SAW-DCE downregulated the expression of vascular endothelial growth factor A in the rat knee cartilage and reduced the formation of"H"type vessels in osteoarthritis rats.SAW-ME could significantly decrease the level of vascular endothelial growth factor in serum of osteoarthritis rats(P<0.05).SAW-DCE could also decrease the level of vascular endothelial growth factor in serum of osteoarthritis rats,but there was no significant change.(2)Both SAW-ME and SAW-DCE significantly inhibited vascular endothelial cell migration and tube formation,and downregulated the expression of Ang1 and Tie2 proteins.(3)Transcriptome sequencing analysis found that abnormal angiogenesis in osteoarthritis was related to the PI3K/AKT signaling pathway.(4)To conclude,SAW-ME and SAW-DCE can inhibit angiogenesis in the rat model of osteoarthritis,and the mechanism may be related to the Ang1/Tie2 and PI3K/AKT signaling pathways.

Objective To explore the correlation between thyroid antibody levels and early renal injury in patients with type 2 diabetes mellitus(T2DM)combined with Hashimoto's thyroiditis(HT).Methods A total of 375 T2DM patients hospitalized in The Affiliated Hospital of Xuzhou Medical University from January 2018 to December 2022 were selectedas the study subjects,and 197 healthy people were selected as the control subjects.The patients with T2DM were divided into simple T2DM group(n=191)and T2DM combined with HT group(HT,n=184).According to the urinary albumin/creatinine ratio(UACR)level,T2DM patients with HT were divided into microalbuminuria subgroup(MUAlb,30≤UACR≤300 mg/g,n=70)and normal albuminuria subgroup(NUAlb,UACR<30 mg/g,n=114).According to whether the thyroid antibody was positive,they were divided into thyroid peroxides antibody[TPOAb(+)]subgroup(n=56),thyroglobulin antibody[TGAb(+)]subgroup(n=40)and TGAb and TPOAb double antibody positive subgroup(n=88).Results Compared with the NC group,the smoking,drinking,urinary creatinine,alpha 1-microglobulin,UACR,FPG,HbA1c,LDL-C,TC,and TG in the HT and T2DM groups increased(P<0.05),while HDL-C decreased(P<0.05).Compared with the NUAlb subgroup,the MUAlb subgroup showed age,DM duration,FPG,HbA1c,TGAb,TPOAb,thyroid stimulating hormone(TSH)increased(P<0.05),while FT3 and eGFR decreased(P<0.05).Spearman correlation analysis showed that UACR was positively correlated with age,HbA1c,TPOAb,TGAb,TSH(P<0.01),and negatively correlated with FT3(P<0.01).The UACR of the TGAb(+)+TPOAb(+)subgroup was higher than that of the TGAb(+)and TPOAb(+)subgroups(P<0.05).Logistic regression analysis showed that TSH,TGAb,TPOAb,and HbA1c were risk factors for MUAlb,while FT3 was a protective factor for MUAlb.Conclusions In T2DM with HT patients with normal thyroid function,TPOAb and TGAb are closely related to the occurrence of early renal injury.

The CRISPR-Cas9 system is composed of a clustered regularly interspaced short palindromic repeat (CRISPR) and its associated proteins, which are widely present in bacteria and archaea, serving as a specific immune protection against viral and phage secondary infections. CRISPR-Cas9 technology is the third generation of targeted genome editing technologies following zinc finger nucleases (ZFNs) and transcription activator like effector nucleases (TALENs). The CRISPR-Cas9 technology is now widely used in various fields. Firstly, this article introduces the generation, working mechanism and advantages of CRISPR-Cas9 technology; secondly, it reviews the applications of CRISPR-Cas9 technology in gene knockout, gene knock-in, gene regulation and genome in breeding and domestication of important food crops such as rice, wheat, maize, soybean and potato. Finally, the article summarizes the current problems and challenges encountered by CRISPR-Cas9 technology and prospects future development and application of CRISPR-Cas9 technology.
Gene Editing ; CRISPR-Cas Systems/genetics* ; Plant Breeding ; Crops, Agricultural/genetics* ; Technology

Objective:To compare the clinical effects of mortice and tenon joint and end-to-end bone contact of zygomatic arch in reduction malarplasty, and to explore the clinical application value of mortice and tenon joint.Methods:The clinical data of patients who underwent reduction malarplasty in Sichuan Friendship Hospital and West China Hospital of Stomatology, Sichuan University from January 2013 to June 2020 were analyzed retrospectively. All patients were treated with classical or modified L-shaped zygomatic arch osteotomy. According to the bone connection mode of the zygomatic arch, the patients were divided into Group Ⅰ and Group Ⅱ. The patients in Group Ⅰ were treated with mortice and tenon joint (from June 2017 to June 2020), and the ones in Group Ⅱ were treated with end-to-end contact (from January 2013 to May 2017). The movement between zygomatic body and zygomatic arch were measured 6-24 months after surgeries. The postoperative satisfaction rate was investigated, and the incidence of complications within 2 years after operation was recorded. The data were statistically analyzed by SPSS 20.0 software. The measurement data were expressed by Mean±SD, and the counting data were expressed by cases (%). T-test was used to compare the age difference, zygomatic body and zygomatic arch movement distance between the two groups. Chi-square test was used to compare the sex composition ratio, postoperative satisfaction rate (sum of very satisfied and satisfied cases/sum of cases in respective group) and incidence of complications between the two groups. P<0.05 was considered statistically significant. Results:A total of 380 patients presenting with zygomatic protrusion were included in this retrospective study. One hundred and ninety patients were included in Group Ⅰ[22 men and 168 women; aged(26.8 ±8.6) years)] and 190 patients in Group Ⅱ [16 men and 174 women; aged (25.2 ±8.8) years)]. There was no significant difference in sex constituent ratio and age between the two groups ( P>0.05). After the operation, the width of the face was narrowed, and the contour of the face was significantly improved. The medial movement distance of zygomatic body in Group Ⅰ and Group Ⅱ was (2.65±0.76) mm versus (2.51±0.78) mm, and the movement distance of zygomatic arch in Group Ⅰ and Group Ⅱ was (4.58 ±0.44) mm versus (2.60±0.28) mm. There was no significant difference in movement distance of zygomatic body between Group Ⅰ and Group Ⅱ ( t=1.77, P=0.077), but there was significant difference in the zygomatic arch ( t=52.33, P<0.001). The satisfaction rate of patients in Group Ⅰ was 75.8% (144/190), which was higher than that in Group Ⅱ (55.3%, 105/190) ( χ2=17.72, P<0.001). There was no significant difference in the incidence of postoperative infection, temporary paresthesia, and hematoma between the two groups ( P>0.05). The incidence of facial asymmetry, sagging cheek, bone suture and nonunion in Group Ⅱ was significantly higher than that in Group Ⅰ ( P<0.05). Conclusion:Compared with end-to-end bone contact in reduction malarplasty, the mortice and tenon joint of the zygomatic arch achieved better facial narrowing effect and long-term stability, higher patient satisfaction rate and less postoperative complications.

Objective:To compare the clinical effects of mortice and tenon joint and end-to-end bone contact of zygomatic arch in reduction malarplasty, and to explore the clinical application value of mortice and tenon joint.Methods:The clinical data of patients who underwent reduction malarplasty in Sichuan Friendship Hospital and West China Hospital of Stomatology, Sichuan University from January 2013 to June 2020 were analyzed retrospectively. All patients were treated with classical or modified L-shaped zygomatic arch osteotomy. According to the bone connection mode of the zygomatic arch, the patients were divided into Group Ⅰ and Group Ⅱ. The patients in Group Ⅰ were treated with mortice and tenon joint (from June 2017 to June 2020), and the ones in Group Ⅱ were treated with end-to-end contact (from January 2013 to May 2017). The movement between zygomatic body and zygomatic arch were measured 6-24 months after surgeries. The postoperative satisfaction rate was investigated, and the incidence of complications within 2 years after operation was recorded. The data were statistically analyzed by SPSS 20.0 software. The measurement data were expressed by Mean±SD, and the counting data were expressed by cases (%). T-test was used to compare the age difference, zygomatic body and zygomatic arch movement distance between the two groups. Chi-square test was used to compare the sex composition ratio, postoperative satisfaction rate (sum of very satisfied and satisfied cases/sum of cases in respective group) and incidence of complications between the two groups. P<0.05 was considered statistically significant. Results:A total of 380 patients presenting with zygomatic protrusion were included in this retrospective study. One hundred and ninety patients were included in Group Ⅰ[22 men and 168 women; aged(26.8 ±8.6) years)] and 190 patients in Group Ⅱ [16 men and 174 women; aged (25.2 ±8.8) years)]. There was no significant difference in sex constituent ratio and age between the two groups ( P>0.05). After the operation, the width of the face was narrowed, and the contour of the face was significantly improved. The medial movement distance of zygomatic body in Group Ⅰ and Group Ⅱ was (2.65±0.76) mm versus (2.51±0.78) mm, and the movement distance of zygomatic arch in Group Ⅰ and Group Ⅱ was (4.58 ±0.44) mm versus (2.60±0.28) mm. There was no significant difference in movement distance of zygomatic body between Group Ⅰ and Group Ⅱ ( t=1.77, P=0.077), but there was significant difference in the zygomatic arch ( t=52.33, P<0.001). The satisfaction rate of patients in Group Ⅰ was 75.8% (144/190), which was higher than that in Group Ⅱ (55.3%, 105/190) ( χ2=17.72, P<0.001). There was no significant difference in the incidence of postoperative infection, temporary paresthesia, and hematoma between the two groups ( P>0.05). The incidence of facial asymmetry, sagging cheek, bone suture and nonunion in Group Ⅱ was significantly higher than that in Group Ⅰ ( P<0.05). Conclusion:Compared with end-to-end bone contact in reduction malarplasty, the mortice and tenon joint of the zygomatic arch achieved better facial narrowing effect and long-term stability, higher patient satisfaction rate and less postoperative complications.

Objective:To compare magnetic resonance imaging (MRI)-based and computed tomography (CT)-based target volume delineation and dose coverage in partial breast irradiation (PBI) for patients with breast cancer, aiming to explore the application value of MRI localization in PBI after breast-conserving surgery.Methods:Twenty-nine patients with early breast cancer underwent simulating CT and MRI scans in a supine position. The cavity visualization score (CVS) of tumor bed (TB) was evaluated. The TB, clinical target volume (CTV), planning target volume (PTV) were delineated on CT and MRI images, and then statistically compared. Conformity indices (CI) between CT- and MRI-defined target volumes were calculated. PBI treatment plan of 40 Gy in 10 fractions was designed based on PTV-CT, and the dose coverage for PTV-MRI was evaluated.Results:The CVS on CT and MRI images was 2.97±1.40 vs. 3.10±1.40( P=0.408). The volumes of TB, CTV, PTV on MRI were significantly larger than those on CT, (24.48±16.60) cm 3vs. (38.00±19.77) cm 3, (126.76±56.81) cm 3vs. (168.42±70.54) cm 3, (216.63±81.99) cm 3vs. (279.24±101.55) cm 3, respectively, whereas the increasing percentage of CTV and PTV were significantly smaller than those of TB. The CI between CT-based and MRI-based TB, CTV, PTV were 0.43±0.13, 0.66±0.11, 0.70±0.09( P<0.001), respectively. The median percentage of PTV-MRI receiving 40 Gy dose was 81.9%(62.3% to 92.4%), significantly lower than 95.6%(95.0%~97.5%) of PTV-CT. Conclusions:The CVS between CT and MRI is not significantly different, but the MRI-based TB, CTV, PTV are significantly larger than CT-based values. The PTV-MRI is of underdose if PBI treatment plan is designed for PTV-CT. As a supplement of CT scan, MRI can enhance the accuracy of TB delineation after breast-onserving surgery.