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Objective:To investigate the changes of T1 and T2 values in residual liver after major liver resection in rats and the relationship with pathologic indices related to liver regeneration.Methods:Seventy healthy male Sprague Dawley rats, SPF grade, aged 7-8 weeks, weighting 250-280 g, were divided into MR scan group ( n=14) and pathologic analysis group ( n=56). The MR scan group was further divided into partial hepatectomy group ( n=7) and the sham operation group ( n=7). MRI T 1 mapping and T 2 mapping were performed before surgery and on day 1, 2, 3, 5, 7, 14, 21 after surgery. T1 and T2 values of liver parenchyma were measured. In the pathologic analysis group, 7 rats were randomly included at each time point before and after surgery for pathologic examination, the diameter and proliferative activity (Ki-67 indices) of hepatocytes were assessed. The changes of imaging and pathologic indices were observed, and the correlations between MR parameters and liver volume and pathologic indices were analyzed. Results:Both T1 and T2 values in liver parenchyma were increased on day 1 after surgery and reached their maximum values on day 2 ( P=0.005 and P<0.001, compared with baseline), then were gradually decreased, and recovered to the preoperative level on day 14 and 21 ( P>0.05), respectively. T2 value was correlated with hepatocyte diameter, liver volume and Ki-67 indices better ( r=0.640, -0.764, 0.765, respectively, all P<0.001). T1 value was correlated with hepatocyte diameter, liver volume and Ki-67 indices ( r=0.472, -0.481 and 0.444, all P<0.001). Conclusion:The T1 and T2 values of rats liver remnant parenchyma showed regular changes, and were correlated with liver regeneration indices, which reflect the microscopic changes of rat liver remnant parenchyma, and are expected to be used for quantitative monitoring of liver remnant regeneration.
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Objective:To understand the results of blind evaluation of dissertation of three-year doctors and eight-year medical doctors, and to explore the improvement measures of eight-year program education.Methods:The data analysis method was manipulated. A total of 47 eight-year doctoral and 88 three-year doctoral dissertations submitted by the first clinical college of Huazhong University of Science and Technology in 2020 were selected as the research material. SPSS 17.0 was used to perform Chi-square test to compare the itemized evaluation opinions of the dissertation, Spearman test was used to analyze the correlation between the defense opinions, itemized evaluation opinions and the overall evaluation.Results:The gap between eight-year and three-year doctoral dissertation is mainly manifested in innovation and research value ( χ2=9.10, P=0.003), topic and review ( χ2=5.70, P=0.017), while there is no significant difference in the overall assessment and oral defense suggestion. The main influencing factor of dissertation defense suggestion for both doctors was the dissertation standardization (eight-year: r s=0.53, P<0.001; three-year: r s=0.45, P<0.001). The evaluation results of eight-year doctor dissertation were closely related to basic knowledge and scientific research ability ( r s=0.74, P<0.001). Conclusion:There is no significant difference between eight-year doctors and full-time doctors in research attitude. But there was a certain gap in scientific research and innovation ability among them. It is suggested to clarify the teaching objectives, formulate and refine the evaluation system of dissertations, and strengthen the cultivation of scientific research interest and academic belief of eight-year study program.
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Background Pterygium is one of the common ocular surface disorders,and the main drugs for pterygium include dexamethasone (DXM),interferon α-2b (IFN-α2b),mitomycin C (MMC),5-fluorouracil (5-FU),cyclosporin A (CsA) and tacrolimus (FKS06).However,the efficacy of these drugs on the fibroblasts from recurrence pterygium is unelucidated.Objective This study was to compare the efficacy of DXM,IFN-o2b,MMC,5-FU,CsA and FK506 on proliferation and apoptosis of recurrent pterygium-derived fibroblasts in vitro.Methods The specimens of recurrence pterygium were collected during surgery in Tianjin Medical University Ophthalmological Hospital from May 2015 to July 2016 under the written informed consent.Fibroblasts were isolated and cultured by explant culture method and identified by immunochemistry.DXM,IFN-α2b,MMC,5-FU,CsA and FK506 were added into the medium for 48 hours,respectively,and the cells cultured without drug were used as the control group.The inhibitory efficiency of different concentrations of DXM,IFN-α2b,MMC,5-FU,CsA and FK506 on the cell proliferation was assayed by cell counting kit-8 (CCK-8),and 50％ inhibiting concentration (IC50) of the drugs was calculated.The cells were treated by the IC50 dose of drugs for 48 hours,and cell apoptotic proportion and cell cycle were assessed by flow cytometry analysis.The expression of proliferating cell nuclear antigen (PCNA) in the cells after treated by drugs was detected by immunochemistry.Results Cultured cells grew well with the fusiform shape and radial arrangement.Vimentine showed the positive expression and keratin was absently expressed in the cells.The IC50 to the cells was (3.5×103±2.83×10-2)mg/L,(6.1×102±3.6×10-3)mg/L,(3.2×10-1±1×10-4)mg/L,(2.2× 101 ± 1.2× 10-3) mg/L,(6.3 × 101 ±2.5 × 10-3) mg/L and (6.0× 101 ± 0.0× 100) mg/L in the DXM,IFN-α2b,MMC,5-FU,CsA and FK506,respectively.In the 48 hours after treated by the IC50 drugs,the apoptotic ratio was (35.00± 3.21)％,(30.37±1.67)％,(26.11±0.75)％,(22.01±0.07)％,(20.95±1.68)％ and (19.85±0.52)％ in the IFN-α2b group,CsA group,MMC group,FK506 group,DXM group and 5-FU group,which was significantly higher than (11.38±2.18) ％ in the control group (all at P＜0.05).The cell proportion of G0/G1 phase,S phase and G2/M phase was (85.64±2.62)％,(5.29±1.56)％ and (2.73-±2.66)％ in the control group,and the cell proportion of G0/G1 phase was reduced,while that of S phase or G2/M phase was considerably increased in various drug groups (all at P＜0.05),with the blocking efficiency of cell cycle was in turn MMC,CsA,5-FU,DXM,IFN-α2b and FK506.The expressional rate of PCNA in the cells was (95.00 ± 2.00) ％,(82.67 ± 5.04) ％,(80.00 ± 2.78) ％,(64.00± 6.55)％,(38.00±3.00)％,(32.00±4.36)％ and (29.67±3.02)％ in the control group,FK506 group,DXM group,5-FU group,IFN-α2b group,CsA group and MMC group,showing a significant difference among the groups (F=25.995,P＜0.01),and the expressional rate of PCNA was significant lower in various drug groups than that in the control group (all at P＜0.05).Conclusions DXM,IFN-α2b,MMC,5-FU,CsA and FK506 are all able to inhibit the proliferation and promote the apoptosis of recurrent pterygium-derived fibroblasts in vitro,and MMC and CsA appear to have a stronger effect.
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In this work, polyelectrolyte microcapsules containing gold nanoparticles were prepared via layer by layer assembly. Gold nanoparticles and poly (allyamine hydrochloride) (PAH) were coated on the CaCO3 microparticles. And then EDTA was used to remove the CaCO3 core. Scanning electron microscopy (SEM) was used to characterize the surface of microcapsules. SEM images indicate that the microcapsules and the polyelectrolyte multilayer were deposited on the surface of CaCO3 microparticles. FITC-bovine serum albumin (FITC-BSA, 2 mg) was incorporated in the CaCO3 microparticles by co-precipitation. Fluorescence microscopy was used to observe the fluorescence intensity of microcapsules. The encapsulation efficiency was (34.31 +/- 2.44) %. The drug loading was (43.75 +/- 3.12) mg g(-1).