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PurposeTo evaluate the correlation between microvascular density (MVD) and intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) parameters and the effect of glycolytic flux after transarterial chemoembolization (TACE) in a rabbit VX2 liver tumor.Materials and methodsVX2 liver tumor allografts in 15 New Zealand white rabbits were treated with sterile saline (control group, n = 5) or lipiodol-doxorubicin emulsion (experimental group, n = 10). MRI was performed 2 weeks after the procedure to evaluate IVIM parameters, including apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (PF). All animal samples were taken of the tumor and surrounding liver. Immunostaining for CD31, CD34, CD105, and VEGF was used to evaluate MVD. The protein expression of Glut4, HK2, PKM2, LDHA, and MCT1 was determined using western blotting. Pearson correlation tests were used to analyze the relationship between MVD and IVIM parameters.ResultsD* value in the peritumoral region was negatively correlated with CD34 (r = –0.71, P = 0.01). PF value positively correlated with CD34 (r = 0.68, P = 0.015), CD105 (r = 0.76, P = 0.004) and VEGF (r = 0.72, P = 0.008) in the peritumoral region. Glut4, HK2, PKM2, and MCT1 in the peritumoral regions were higher in the experimental group than in the control group (all P < 0.05).ConclusionIVIM parameters were correlated with MVD in the intratumoral and peritumoral regions after TACE in a rabbit liver tumor model. The angiogenesis reflected by MVD may be related to changes of glycolytic flux.

In this study, we sought to evaluate changes in peritumoral fibrosis after transarterial chemoembolization (TACE) in a rabbit VX2 liver tumor model using intravoxel incoherent motion diffusion-weighted imaging (IVIM DWI) and ultrasound shear wave elastography (SWE). A total of 20 rabbits underwent implantation of VX2 tumor tissues in the left lobe of the liver. The rabbits were randomly divided into an experimental group (n = 10) or a control group (n = 10). Those in the experimental group were treated with an emulsion of lipiodol and pirarubicin through a microcatheter 2–3 weeks after implantation; those in the control group were treated with sterile water. Compared with the control group, the true diffusion coefficient (D) and pseudodiffusion coefficient (D*) values in liver tissues were significantly lower (p < 0.05 for all) and liver stiffness values (LSV) (10.58 ± 0.89 kPa) were higher in the experimental group (7.65 ± 0.86 kPa; p < 0.001). The median stage of liver fibrosis based on METAVIR scores was 1 (1,1) in the control group and 2 (2,3) in the experimental group (Z = 4.15, p < 0.001). D, D*, and LSV were significantly correlated with pathologic staining in the assessment of liver fibrosis (r = −0.54 p = 0.015; r = −0.50, p = 0.025; r = 0.91, p < 0.001; respectively). These data suggest that TACE aggravates liver injury and liver fibrosis, especially surrounding the tumor, in a rabbit VX2 liver tumor model. IVIM DWI and SWE can be used to evaluate the change in liver fibrosis.

In this study,we sought to evaluate changes in peritumoral fibrosis after transarterial chemoembolization (TACE) in a rabbit VX2 liver tumor model using intravoxel incoherent motion diffusion-weighted imaging (IVIM DWI) and ultrasound shear wave elastography (SWE). A total of 20 rabbits underwent implantation of VX2 tumor tissues in the left lobe of the liver. The rabbits were randomly divided into an experimental group (n = 10) or a control group (n =10).Those in the experimental group were treated with an emulsion of lipiodol and pirarubicin through a microcatheter 2--3 weeks after implantation; those in the control group were treatedwith sterilewater. Comparedwith the control group, the true diffusion coefficient (D) and pseudodiffusion coefficient (D*) values in liver tissues were significantly lower (p < 0.05 for all) and liver stiffness values (LSV) (10.58 ± 0.89 kPa) were higher in the experimental group (7.65 ± 0.86 kPa; p < 0.001). The median stage of liver fibrosis based onMETAVIR scoreswas 1 (1,1) in the control group and 2 (2,3) in the experimental group (Z =4.15,p < 0.001). D, D*, and LSV were significantly correlated with pathologic staining in the assessment of liver fibrosis (r = -0.54 p = 0.015; r = -0.50, p = 0.025; r =0.91,p < 0.001; respectively). These data suggest that TACE aggravates liver injury and liver fibrosis, especially surrounding the tumor, in a rabbit VX2 liver tumor model. IVIM DWI and SWE can be used to evaluate the change in liver fibrosis. [ABSTRACT FROM AUTHOR]

The digital beam position monitor processer (DBPM) is one of the important beam diagnosis equipments in particle accelerator and it will be massproduced during the construction of Upgrade of Beijing Electron Positron Collider (BEPCⅡ) and high energy photon source (HEPS), which brings great challenges to the testing work. The analog to digital converter (ADC) module is an essential component of DBPM and its conversion accuracy determines the resolution of the beam position measurement. Therefore, in order to ensure that these two projects meet the design targets, it is necessary to test the ADC performance. Its main observation object includes the phaselocked loop, sampling clock jitter, signaltonoise ratio (SNR), etc. To meet the batch test requirements of the selfdeveloped DBPM ADC, a method of testing the sampling performance based on the histogram was proposed. The histogram’s test principle is that the shape of the histogram can detect whether the sampling clock is phaselocked to the input signal, the boundary value of the histogram reflects the amplitude of the input signal to judge if the ADC is saturated, and the average and standard deviation of the data peak on the histogram can be used to calculate the clock jitter that conforms to the normal distribution. In this paper, the mathematical relation between the statistics of each data peak, clock jitter, and SNR was simulated by MATLAB in the situation of phaselocking. The separation algorithm was designed to obtain the data corresponding to each peak of the histogram and compute the clock jitter and SNR. An integrated test platform was built and experiments were carried out to verify the testing effect of the histogram method. The experimental results show that when the amount of sampling data is appropriate, the histogram method can complete the test quickly and accurately, and the measurement result is close to that of the highperformance phase noise analyzer. The clock jitter measurement error is less than 200 fs, the SNR measurement error is less than 2 dB, and the entire test duration is less than 1 min, which fulfills large volume testing demands. Compared with the manual instrument measure method, the histogram approach is simpler and lower cost to test with the same order of magnitude accuracy and has been implemented by programming to reduce labor intensity. The test program has been implemented in the automatic test platform and used to batch detection of DBPM products successfully.