Improving the diagnostic performance of computed tomography angiography for intracranial large arterial stenosis by a novel super-resolution algorithm based on multi-scale residual denoising generative adversarial network.

BACKGROUND: Computed tomography angiography (CTA) is very popular because it is characterized by rapidity and accessibility. However, CTA is inferior to digital subtraction angiography (DSA) in the diagnosis of intracranial artery stenosis or occlusion. DSA is an invasive examination, so we optimized the quality of cephalic CTA images. METHODS: We used 5000 CTA images to train multi-scale residual denoising generative adversarial network (MRDGAN). And then 71 CTA images with intracranial large arterial stenosis were treated by Super-Resolution based on Generative Adversarial Network (SRGAN), Enhanced Super-Resolution based on Generative Adversarial Network (ESRGAN) and post-trained MRDGAN, respectively. Peak signal-to-noise ratio (PSNR) and structural similarity index measurement (SSIM) of the SRGAN, ESRGAN, MRDGAN and original CTA images were measured respectively. The qualities of MRDGAN and original images were visually assessed using a 4-point scale. The diagnostic coherence of digital subtraction angiography (DSA) with MRDGAN and original images was analyzed. RESULTS: The PSNR was significantly higher in the MRDGAN CTA images (35.96 ± 1.51) than in the original (31.51 ± 1.43), SRGAN (25.75 ± 1.18) and ESRGAN (30.36 ± 1.05) CTA images (all P < 0.001). The SSIM was significantly higher in the MRDGAN CTA images (0.95 ± 0.02) than in the SRGAN (0.88 ± 0.03) and ESRGAN (0.90 ± 0.02) CTA images (all P < 0.01). The visual assessment was significantly higher in the MRDGAN CTA images (3.52 ± 0.58) than in the original CTA images (2.39 ± 0.69) (P < 0.05). The diagnostic coherence between MRDGAN and DSA (κ = 0.89) was superior to that between original images and DSA (κ = 0.62). CONCLUSION: Our MRDGAN can effectively optimize original CTA images and improve its clinical diagnostic value for intracranial large artery stenosis.

South China Sea documents the transition from wide continental rift to continental break up.

During extension, the continental lithosphere thins and breaks up, forming either wide or narrow rifts depending on the thermo-mechanical state of the extending lithosphere. Wide continental rifts, which can reach 1,000 km across, have been extensively studied in the North American Cordillera and in the Aegean domain. Yet, the evolutionary process from wide continental rift to continental breakup remains enigmatic due to the lack of seismically resolvable data on the distal passive margin and an absence of onshore natural exposures. Here, we show that Eocene extension across the northern margin of the South China Sea records the transition between a wide continental rift and highly extended (<15 km) continental margin. On the basis of high-resolution seismic data, we document the presence of dome structures, a corrugated and grooved detachment fault, and subdetachment deformation involving crustal-scale nappe folds and magmatic intrusions, which are coeval with supradetachment basins. The thermal and mechanical weakening of this broad continental domain allowed for the formation of metamorphic core complexes, boudinage of the upper crust and exhumation of middle/lower crust through detachment faulting. The structural architecture of the northern South China Sea continental margin is strikingly similar to the broad continental rifts in the North American Cordillera and in the Aegean domain, and reflects the transition from wide rift to continental breakup.

Radiofrequency ablation does not induce the significant increase of CD4(+) CD25(+) Foxp3(+) regulatory T cells compared with surgical resection in Hepal-6 tumor model.

Surgical resection (SR) and radiofrequency ablation (RFA) are all currently recognized as important and effective treatment in solid tumors. This study aimed to investigate change in level of CD4(+) CD25(+) Foxp3(+) regulatory T (Treg) cells in tumor-bearing mice after SR vs. RFA and the relationship of this level with tumor progression. Hepa1-6 tumor cells were inoculated subcutaneously into C57BL/6J mice. The population of Treg cells was measured by flow cytometry at selected post-SR or post-RFA times. Tumor growth was measured by rechallenge in the contralateral flank. The tumor volume was calculated and compared with that of a control group. The correlation between the population of Treg cells and tumor volume was analyzed. A significant increase in Treg cells was observed after SR compared with the preoperative level, while the level after RFA was relatively stable. A significant difference in tumor growth between the SR and RFA groups was observed in the initial postoperative phase but not in the later phase. A correlation was found between tumor volume and level of Treg cells. Our study revealed that RFA stabilizes the level of Treg during postoperative recovery, whereas SR activates the immunosuppressive reaction by upregulating the level of such cells, promoting tumor growth.

Preoperative levels of serum interleukin-6 in patients with hepatocellular carcinoma.

BACKGROUND/AIMS: A high prevalence of serum IL-6 has been associated with the pathogenesis of hepatocellular carcinoma (HCC) in both animals and humans. However, it is not clear how the levels of serum IL-6 influence the prognosis of HCC patients. This study was carried out in order to attempt to answer this question. METHODOLOGY: A total of 156 adults were selected and categorized into four groups: healthy subjects (n=18), those with tumor recurrence (n=26), those initially diagnosed with HCC (n=32), and those with HCC (n=80) who received curative resection between 2002 and 2004 with five years of follow-up. Serum IL-6 levels were determined in all subjects by the same ELISA method. RESULTS: IL-6 was found in high levels in the serum of patients initially diagnosed with HCC (8.47±5.92, p<0.0001) and in patients with HCC and tumor recurrence (12±31.90, p=0.001) compared with healthy subjects (0.89±1.51). This includes all patients who received therapy between 2007 and 2008. The levels of serum IL-6 were positively correlated with tumor size (p=0.002) in the HCC patients who received curative resection between 2002 and 2004 with five years of follow-up. CONCLUSIONS: High levels of serum IL-6 correlated positively with tumor size and with poor prognosis in HCC patients.

Dendritic cells-mediated CTLs targeting hepatocellular carcinoma stem cells.

Immunotherapy, especially using dendritic cells (DCs)-based vaccine, appears promising in the treatment of hepatocellular carcinoma (HCC) following surgery. However, the therapeutic efficacy of current DC vaccines loaded with HCC antigen is limited in clinical practice. One important reason might be that the DC vaccines for the treatment of HCC were not aimed at targeting the hepatocellular carcinoma cancer stem cells (HCCCSCs). Therefore, establishing an immunotherapy to kill HCC stem cells could be a novel therapeutic strategy. In this study, we have developed an immunotherapy to target CD133(+) HCC cells in the treatment of HCC. This study had three main findings; (1) CD133(+)HCC cells RNA loaded DCs could induce special CD8(+) cytotoxic T lymphocytes (CD133(+)Huh7-CTLs) response against CD133(+) Huh7 cells in vitro. (2) Huh7 cells-induced tumor growth in vivo was effectively inhibited by CD133(+)Huh7-CTLs. (3) the great inhibition potential of CD133(+)Huh7-CTLs to Huh7-induced tumor growth might not be only associated with anti-tumor cytokines such as IFNγ, but also to CD133(+)Huh7-DCs induced specific CTLs. This study shows an experimental proof that CD133(+)HCC cells RNA loaded DC vaccine has potential in treating HCC and may provide a new therapy for clinical post operative adjuvant therapy in future.

Increased intratumoral IL-17-producing cells correlate with poor survival in hepatocellular carcinoma patients.

BACKGROUND/AIMS: To characterize IL-17-producing cells, a newly defined T helper cell subset with potent pro-inflammatory properties, in hepatocellular carcinoma (HCC) and to determine their prognostic values. METHODS: One hundred and seventy-eight HCC patients were enrolled randomly. Distribution and phenotypic features of IL-17-producing cells were determined by flow cytometry and/or immunohistochemistry. RESULTS: Compared with corresponding non-tumor regions, the levels of Th17 cells were significantly increased in tumors of HCC patients (P<0.001). Most intratumoral Th17 cells exhibited an effector memory phenotype with increased expression of CCR4 and CCR6. Intratumoral IL-17-producing cell density was associated with overall survival (OS, P=0.001) and disease-free survival (DFS, P=0.001) in HCC patients. Multivariate Cox analysis revealed that intratumoral IL-17-producing cell density was an independent prognostic factor for OS (HR=2.351, P=0.009) and DFS (HR=2.256, P=0.002). Moreover, the levels of intratumoral Th17 cells were positively correlated with microvessel density in tumors (r=0.616, P=0.001). CONCLUSION: Accumulation of intratumoral IL-17-producing cells may promote tumor progression through fostering angiogenesis, and intratumoral IL-17-producing cell could serve as a potential prognostic marker and a novel therapeutic target for HCC.

[Inhibitory effects of human AFP-derived peptide-pulsed dendritic cells on mouse hepatocellular carcinoma].

BACKGROUND & OBJECTIVE: Alpha-fetoprotein (AFP) is a good candidate antigen for the immunotherapy of hepatocellular carcinoma (HCC). How to overcome the immune tolerance induced by autologous antigen is one of key points for inducing effective antitumor immune reaction. This research was to investigate the effect of human AFP-derived peptide-pulsed dendritic cells (hAFP-DCs) on immunity against mouse HCC. METHODS: Bone marrow-originated DCs were prepared routinely. The activity of hAFP-DC-stimulated cytotoxic T lymphocyte (CTL) against Hepa1-6 cells was examined by MTT assay. C57BL/6 mice were inoculated subcutaneously with 7 x 10(6) Hepa1-6 cells to develop hepatoma, and received intratumor injection of hAFP-DCs, DCs and PBS, respectively, twice a week. Tumor volume was evaluated and the survival of mice after inoculation was observed. RESULTS: We successfully prepared DCs from bone marrow of mice. The cytotoxic activity of CTLs stimulated by hAFP-DCs and DCs showed stronger tendency than that of control, but without significance. The mean tumor volume at 31 days after inoculation with Hepa1-6 cells was (195.04+/-155.22) mm3 in hAFP-DCs group, (360.65+/-209.02) mm3 in DCs group and (756.19+/-503.24) mm3 in PBS group. The differences among these three groups were significant (P < 0.001). The survival rate of mice at 40 days after inoculation was 100% in hAFP-DCs group, 90% in DCs group and 50% in PBS group (P=0.008). CONCLUSION: Human AFP-derived peptide-pulsed DCs can efficiently enhance immunity against HCC in mice.

[Effectiveness of radiofrequency ablation combined with transcatheter arterial chemoembolization for hepatocellular carcinoma].

OBJECTIVE: To analyze the short-term and long-term effectiveness of radiofrequency ablation (RFA) combined with transcatheter arterial chemoembolization (TACE) in the treatment of hepatocellular carcinoma (HCC). METHODS: The clinical data of 114 HCC patients, 104 males and 10 females, aged 55 (30 - 81), treated by RFA combined with TACE and followed up for 20 (1 - 82) months were analyzed. RESULTS: Complete necrosis was achieved in 101 patients (88.6%). 10 patients showed incomplete necrosis and 3 patients showed new neoplasm, and they all underwent repeated RFA or TACE. No therapy-relative death was found. The overall 1-, 2-, 3-, 4-, and 5-year survival rates were 90.4%, 82.6%, 73.2%, 63.5%, and 49.1%respectively. The 1-, 2-, 3-, 4-, and 5-year tumor progression-free survival rates were 77.1%, 64.6%, 54.6%, 46.8%, and 36.4% respectively. The overall 1-, 2-, 3-, 4-, and 5-year survival rates for the tumors with the size < or = 5 cm and the tumors with the size of 5.1 - 7 cm were 95.5%, 84.6%, 73.1%, 61.5%, and 50.6% and 80.2%, 64.9%, 56.3%, 45.3%, and 39.5% respectively (P = 0.041). The overall 1-, 2-, 3-, 4-, and 5-year survival rates for the solitary tumor and multiple tumors (no more than 3 tumors) were 95.8%, 89.1%, 78.1%, 67.1%, and 56.7% and 80.0%, 60.6%, 46.6%, 33.4%, and 21.5% respectively (P = 0.001). The levels of albumin and alpha-fetoprotein, and boundary and number of tumors were proved to be independent risk factors of survival. CONCLUSION: RFA combined with TACE is an effective treatment for HCC with satisfactory short-term and long-term effects, especially for the patients with tumor of the size of 5.1 - 7 cm or multiple lesions.

[Percutaneous radiofrequency ablation combined with other minimally invasive treatments for recurrent hepatocellular carcinoma after hepatectomy].

OBJECTIVE: To evaluate the efficacy and safety of percutaneous radiofrequency ablation (PRFA) and combined with other minimally invasive treatments for recurrent hepatocellular carcinoma (RHCC) after hepatectomy. METHODS: Eighty-four patients with RHCC after hepatectomy who were treated with PRFA or combined with other minimally invasive therapies between August 1999 and February 2008 were analyzed retrospectively. RESULTS: There was no treatment related mortality in the study population, and the morbidity was 2.4% (2/84). The complete ablation rate was 94.0% (79/84), and the 1-, 3- and 5-year overall survival rates were 74.9%, 54.9% and 48.2%, respectively. The 1-, 3- and 5-year overall survival rates of patients with recurrent interval after hepatectomy less than 1 year and over 1 year were 72.1%, 36.2%, 24.2% and 76.8%, 70.6% and 65.1%, respectively (P = 0.040). The 1-, 3- and 5-year overall survival rates of patients with tumor size 3 cm were 83.2%, 67.7%, 67.7% and 59.1%, 24.2%, 12.1%, respectively (P = 0.003). The 1-, 3- and 5-year overall survival rates of patients treated with PRFA alone and combined with percutaneous ethanol injection (PEI) were 66.7%, 33.3%, 22.2% and 76.5%, 57.3%, 57.3%, respectively (P = 0.017). The 1-, 3- and 5-year overall survival rates of patients treated with PRFA alone and combined with transcatheter hepatic arterial chemoembolization (TACE) were 55.6%, 24.7%, 24.7% and 81.6%, 66.0%, 57.5%, respectively (P = 0.001). CONCLUSIONS: PRFA is an effective and safe treatment for RHCC, and tumor size and recurrent interval after hepatectomy are important prognostic factors. Combination with PEI or TACE may improve the efficacy of PRFA for treatment of RHCC.