Generation of functional hepatocyte-like cells from human bone marrow mesenchymal stem cells by overexpression of transcription factor HNF4α and FOXA2.

BACKGROUND: Our previous study showed that overexpression of hepatocyte nuclear factor 4α (HNF4α) could directly promote mesenchymal stem cells (MSCs) to differentiate into hepatocyte-like cells. However, the efficiency of hepatic differentiation remains low. The purpose of our study was to establish an MSC cell line that overexpressed HNF4α and FOXA2 genes to obtain an increased hepatic differentiation efficiency and hepatocyte-like cells with more mature hepatocyte functions. METHODS: Successful establishment of high-level HNF4α and FOXA2 co-overexpression in human induced hepatocyte-like cells (hiHep cells) was verified by flow cytometry, immunofluorescence and RT-PCR. Measurements of albumin (ALB), urea, glucose, indocyanine green (ICG) uptake and release, cytochrome P450 (CYP) activity and gene expression were used to analyze mature hepatic functions of hiHep cells. RESULTS: hiHep cells efficiently express HNF4α and FOXA2 genes and proteins, exhibit typical epithelial morphology and acquire mature hepatocyte-like cell functions, including ALB secretion, urea production, ICG uptake and release, and glycogen storage. hiHep cells can be activated by CYP inducers. The percentage of both ALB and α-1-antitrypsin (AAT)-positive cells was approximately 72.6%. The expression levels of hepatocyte-specific genes (ALB, AAT, and CYP1A1) and liver drug transport-related genes (ABCB1, ABCG2, and SLC22A18) in hiHep cells were significantly higher than those in MSCs-Vector cells. The hiHep cells did not form tumors after subcutaneous xenograft in BALB/c nude mice after 2 months. CONCLUSION: This study provides an accessible, feasible and efficient strategy to generate hiHep cells from MSCs.

Early prediction of survival in hepatocellular carcinoma patients treated with transarterial chemoembolization plus sorafenib.

AIM: To identify clinical biomarkers that could early predict improved survival in patients with advanced-stage hepatocellular carcinoma (HCC) treated with transarterial chemoembolization combined with sorafenib (TACE-S). METHODS: We retrospectively evaluated the medical records of consecutive patients with advanced-stage HCC who underwent TACE-S from January 2012 to December 2015. At the first follow-up 4-6 wk after TACE-S (median, 38 d; range, 33-45 d), patients exhibiting the modified Response Evaluation Criteria in Solid Tumors (mRECIST)-evaluated complete response, partial response, and stable disease were categorized as early disease control. At this time point, multiple variables were analyzed to identify the related factors affecting survival. RESULTS: Ninety-five patients were included in this study, and 60 of these patients achieved early disease control, with an overall disease control rate (DCR) of 63.2%. Patients who got sorafenib at the first TACE (no previous TACE) and patients without portal vein tumor thrombus (PVTT) had a higher DCR than those who underwent previous TACE before TACE-S (72.4% vs 48.6%, P = 0.019) and those with PVTT (75.5% vs 50.0%, P = 0.010). Early disease control after TACE-S, no previous TACE, and no PVTT were the independent prognostic factors for survival in the uni- and multivariate analyses. CONCLUSION: The first follow-up 4-6 wk after TACE-S can be used as the earliest time point to assess the response to TACE-S, and patients with mRECIST-evaluated early disease control, no previous TACE, and no PVTT had better survival.

Tardus parvus waveforms in Doppler ultrasonography for hepatic artery stenosis after liver transplantation: can a new cut-off value guide the next step?

PURPOSE: Considering the high false-positive diagnosis of the tardus parvus waveform (TPW) in Doppler ultrasonography (DUS) for hepatic artery stenosis (HAS) after liver transplantation (LT), this study aimed to determine clinical features and new cut-off values to help guide treatment. MATERIALS AND METHODS: This retrospective study was approved by an Institutional Review Board. A total of 171 LT recipients were included and underwent DUS and either computed tomography angiography or digital subtraction angiography with an interval < 4 weeks at least 1 month post-LT. The DUS of 69 patients exhibited TPW [defined as resistive index (RI) < 0.5 and systolic acceleration time (SAT) > 0.08 s]. A multilevel likelihood ratio (LR) analysis was used to explore new cut-off values for DUS. In addition, abnormal liver function was considered additional evidence (defined as any liver enzyme > 3-fold of the upper limit of normal level or 2-fold increased). The results were stratified into three categories, category 1 (subjects with traditional TPW), category 2 (subjects with traditional TPW and abnormal liver function), and category 3 (subjects with traditional TPW and abnormal liver function, or with new cut-off values), and the diagnostic performance of each category was analyzed. RESULTS: The LR analysis revealed new cut-off values of RI < 0.4 (LR = 10.58) or SAT > 0.12 s (LR = 16.46). The false-positive rates for categories 2 and 3 were significantly lower (7.6% vs. 18.1%, P = 0.038; 1.9% vs. 18.1%, P < 0.001, respectively) than those for category 1, while the sensitivity for category 2 was significantly lower (41.8% vs. 74.6%, P < 0.001; 41.8% vs. 61.2%, P = 0.038, respectively) than that for categories 1 and 3. CONCLUSION: Using either (1) RI < 0.4 or SAT > 0.12 s, or (2) traditional TPW (RI < 0.5 and SAT > 0.08 s) in the presence of abnormal liver functions as the DUS criteria for HAS will significantly decrease the false-positive rate compared to traditional TPW without a significant increase in the false-negative rate.

Improvement of ablative margins by the intraoperative use of CEUS-CT/MR image fusion in hepatocellular carcinoma.

BACKGROUND: To assess whether intraoperative use of contrast-enhanced ultrasound (CEUS)-CT/MR image fusion can accurately evaluate ablative margin (AM) and guide supplementary ablation to improve AM after hepatocellular carcinoma (HCC) ablation. METHODS: Ninety-eight patients with 126 HCCs designated to undergo thermal ablation treatment were enrolled in this prospective study. CEUS-CT/MR image fusion was performed intraoperatively to evaluate whether 5-mm AM was covered by the ablative area. If possible, supplementary ablation was applied at the site of inadequate AM. The CEUS image quality, the time used for CEUS-CT/MR image fusion and the success rate of image fusion were recorded. Local tumor progression (LTP) was observed during follow-up. Clinical factors including AM were examined to identify risk factors for LTP. RESULTS: The success rate of image fusion was 96.2% (126/131), and the duration required for image fusion was 4.9 ± 2.0 (3-13) min. The CEUS image quality was good in 36.1% (53/147) and medium in 63.9% (94/147) of the cases. By supplementary ablation, 21.8% (12/55) of lesions with inadequate AMs became adequate AMs. During follow-up, there were 5 LTPs in lesions with inadequate AMs and 1 LTP in lesions with adequate AMs. Multivariate analysis showed that AM was the only independent risk factor for LTP (hazard ratio, 9.167; 95% confidence interval, 1.070-78.571; p = 0.043). CONCLUSION: CEUS-CT/MR image fusion is feasible for intraoperative use and can serve as an accurate method to evaluate AMs and guide supplementary ablation to lower inadequate AMs.

Contrast-Enhanced Sonography for Diagnosing Collateral Transformation of the Hepatic Artery After Liver Transplantation.

OBJECTIVES: To determine the contrast-enhanced sonographic features of hepatic artery collateral transformation in patients with hepatic artery complications after liver transplantation. METHODS: Ninety-nine liver transplant recipients who underwent contrast-enhanced sonography were recruited from April 2004 to May 2014. The reference standards were conventional angiography and computed tomographic angiography. The contrast-enhanced sonographic features of the hepatic artery in patients with and without collateral arteries were retrospectively analyzed. RESULTS: All 15 patients with hepatic artery collateral transformation had hepatic artery thrombosis (10 of 15) or hepatic artery stenosis (5 of 15). The collateral artery detection rate on contrast-enhanced sonography was 100%. The peripheral hepatic artery could not be visualized by contrast-enhanced sonography in most of the patients with hepatic artery collateral transformation (14 of 15). Additionally, many small tortuous collateral arteries in the porta hepatis region were visualized during the arterial and early portal phases, showing reticulated/patchy (15 of 15) and striped (3 of 15) enhancement patterns on contrast-enhanced sonography. CONCLUSIONS: Collateral transformation of the hepatic artery in patients with hepatic artery complications after liver transplantation appears to have characteristic features on contrast-enhanced sonography, especially a reticulated or patchy enhancement pattern in the porta hepatis region during the arterial and early portal phases combined with the absence of the peripheral hepatic artery. Contrast-enhanced sonography may be a novel method for diagnosing hepatic artery collateral transformation, which may be a highly specific sign of hepatic artery thrombosis or stenosis.

Role of multi-detector computed tomography for biliary complications after liver transplantation.

AIM: To investigate the diagnostic performance of multi-detector computed tomography (MDCT) in detecting biliary complications after orthotopic liver transplantation (OLT). METHODS: Eighty-three consecutive OLT recipients, who presented with clinical or biochemical signs of biliary complications, underwent MDCT examination. Two experienced radiologists assessed MDCT images in consensus to determine biliary complications. Final confirmation was based on percutaneous transhepatic cholangiography or endoscopic retrograde cholangiography in 58 patients, surgery in four patients, liver biopsy in 10, and clinical and sonography follow-up in 11 patients. RESULTS: Biliary complications were eventually confirmed in 62 of 83 patients (74.7%), including anastomotic biliary strictures in 32, nonanastomotic biliary strictures in 21, biliary stones in nine (5 with biliary strictures), anastomotic bile leak in five, and biloma in six (all with nonanastomotic strictures, and 2 with biligenic hepatic abscess). Twenty-one patients had no detection of biliary complications. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of MDCT for detecting biliary strictures were 90.6%, 86.7%, 89.2%, 92.3% and 83.9%, respectively. For detecting biliary stones, anastomotic bile leak and biloma, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of MDCT were all 100%. CONCLUSION: MDCT is a useful screening tool for detecting biliary complications after OLT.

Renal aspergillosis after liver transplantation: clinical and imaging manifestations in two cases.

Renal aspergillosis (RAsp) is a rare complication in liver transplant (LT) recipients. Here we report RAsp in two LT recipients. In both patients, RAsp occurred more than 90 d after allogenetic orthotropic LT, and all the clinical findings were unspecific. RAsp involved unilateral kidney in Case one and bilateral kidneys in Case two. Both computed tomography (CT) and magnetic resonance imaging (MRI) revealed renal abscesses, with progressively enhanced walls and separations and unenhanced alveolate areas after contrast agent administration. On unenhanced CT images they showed inhomogeneous hypo-attenuation. On fat-suppressed T2-weighted images (T2WIs), the walls and separations of the abscesses showed slightly low signal intensity and the central parts of the lesions showed slightly high signal intensity. Both on CT and MRI, there were some hints of renal infarction or chronic ischemia. Both cases were treated by radical nephrectomy followed by adjuvant antifungal treatment. They all recovered well.

[Clinical observation of transcatheter arterial chemoembolization plus sorafenib in the treatment of advanced hepatocellular carcinoma with different types of portal vein tumor thrombosis].

OBJECTIVE: To explore the efficacy and safety of transcatheter arterial chemoembolization (TACE) plus sorafenib in the treatment of advanced hepatocellular carcinoma with different types of portal vein tumor thrombosis. METHODS: A total of 32 patients of advanced hepatocellular carcinoma with tumor thrombosis in portal vein were retrospectively analyzed. All of them took oral sorafenib after TACE. They were divided into 3 groups according to imaging examinations of tumor thrombosis in portal vein. Tumor thrombosis in main portal vein was group A, tumor thrombosis in right/left portal branch group B and tumor thrombosis in the second branch of portal vein group C. Tumor response rate, disease control rate (DCR), overall survival (OS) and time to tumor progression (TTP) was followed up. Liver functions were compared with the pre-treatment level. The occurrences of adverse events were recorded. RESULTS: DCR was 20.0% (Group A), 70.0% (Group B) and 91.7 % (Group C) at 2 months post-treatment. DCR in groups B and C had significant differences with group A (P < 0.05). The median OS was 3 (Group A), 9 (Group B) and 14 months (Group C) and the median TTP 0 (Group A), 3 (Group B) and 6 months (Group C) respectively. The median OS and median TTP were significantly longer in Groups B and C than those in Group A (P < 0.05). Liver function at 2 months post-treatment had no statistical difference with the baseline. The most common adverse effects included hand foot skin reaction (n = 23, 3 cases of grade 3), hypertension (n = 3), diarrhea (n = 25, 3 cases of grade 3), hair loss (n = 12), oral ulcers (n = 1) and gastrointestinal bleeding (n = 2). CONCLUSION: The combined use of TACE and sorafenib is both safe and efficacious in the treatment of advanced hepatocellular carcinoma with tumor thrombosis in portal vein. And it may prolong OS and TTP in hepatocellular carcinoma with tumor thrombosis in right/left portal vein and second branch of portal vein.

[Evaluation of graft perfusion in patients with ischemic-type of biliary lesions after liver transplantation].

OBJECTIVE: To investigate the value of 320-rows CT perfusion (CTP) imaging in the study of hepatic hemodynamic characters in ischemic-type biliary lesions (ITBL) after liver transplantation. METHODS: A total of 11 ITBL patients received 320-slice CT angiography (CTA) and CTP after liver transplantation scheduled at 5-10 min away. Four patients underwent liver biopsy While 7 patients with normal liver after transplantation were selected as the control group. The parameters of hepatic artery perfusion (HAP), portal vein perfusion (PVP), total hepatic perfusion (TLP) and hepatic arterial perfusion index (HPI) were measured and compared for all patients. And the blood perfusion characters of liver with ITBL after transplantation were analyzed. RESULTS: (1) In 11 ITBL patients, 3 patients had no vascular complications on CTA, 1 with simple hepatic artery stenosis (HAS), 1 with HAS and arterioportal shunt (APS), 2 with HAS and portal vein stenosis/right hepatic vein stenosis (PVS/RHVS), 1 with simple APS, 2 with simple PVS and 1 with portal vein thrombosis and cavernous transformation of portal vein (PVT and CTPV). And 4/11 patients underwent liver biopsy, 2 in which confirmed mild acute rejection and 2 confirmed biliary obstruction associated with ascending biliary infection.(2) HAP of the ITBL and control groups were (66 ± 38) and (40 ± 8) ml×min(-1)·(100 ml)(-1), PVP (128 ± 35) and (163 ± 21) ml×min(-1)·(100 ml)(-1), TLP (194 ± 58) and (203 ± 19) ml×min(-1)·(100 ml)(-1), HPI 34% ± 14% and 21% ± 4% respectively. The differences in the value of HAP, PVP and HPI between the groups were statistically significant (P < 0.05) excluding TLP. CONCLUSION: Various liver perfusion abnormalities of ITBL may be evaluated objectively by CTP. ITBL might occurred when HAP and HPI increased with a decreased of PVP.

[The diagnosis and treatment of isolated celiac and superior mesenteric artery dissection: 2 cases report and literature review].

OBJECTIVE: To investigate the diagnosis and treatment of isolated celiac artery (CA) dissection and superior mesenteric artery (SMA) dissection. METHODS: Integrating clinical data of 119 cases with isolated dissection of the visceral arteries (IDVA) reported in literature and 2 patients with spontaneous isolated dissections of both CA and SMA treated in the Third Affiliated Hospital of Sun Yat-sen University, the diagnosis and treatment of IDVA were analyzed retrospectively. RESULTS: Among 119 cases reported in the literature, 69 cases were symptomatic. All of the cases were diagnosed by contrast-enhanced abdominal CT or MRI. After IDVA was discovered, surgical treatment and endovascular stent placement was performed in 8 and 5 patients respectively, although the remaining 106 patients were managed conservatively with good results. In our 2 cases, the diagnosis of CA and SMA dissection was established by contrast-enhanced CT and confirmed by conventional angiography. One patient was treated with anticoagulation and antihypertension, and the other patient was treated with endovascular stenting. Both of the patients didn't have discomfort during the follow-up period of 12 and 3 months respectively. CONCLUSIONS: Contrast-enhanced abdominal CT is the main tool for detection of IDVA. Most of the patients with IDVA can be managed conservatively, but close surveillance with imaging studies is necessary for early recognition of dissection progression. Patients with persistent or relapsed symptoms, and dissection progression, should undergo surgical or endovascular treatment.

[Labeling of liver cancer cell for fluorescence imaging study by far-red fluorescence protein reporter gene mKate2].

OBJECTIVE: To create far-red fluorescence protein reporter gene mKate2 lentivirus, label human liver cancer cell line HepG2 with lentivirus and explore the feasibility of in vitro fluorescence imaging of labeled tumor cells so as to provide experimental rationales for in vivo fluorescence tumor imaging. METHODS: mKate2 gene was amplified from pmKate2-N plasmid. Then the fragment was inserted into the lentivirus expression vector pLenti6.3/V5-DEST. The expression plasmids pLenti6.3-mKate2 and the packaging plasmids were cotransfected into 293T cells. The biological titer of lentivirus was determined. HepG2 cells were infected with mKate2 lentivirus at a MOI (virus multiplicity of infection) of 6 for 96 hours. The infection efficiency was assayed through fluorescence microscope and fluorescent-activated cell scanning (FACS). And 2 × 10(6) mKate2-HepG2 cells were collected for fluorescence imaging through an optical imaging system. And the optimal imaging parameters were determined. RESULTS: DNA sequencing analysis confirmed that mKate2 gene sequence was correct and there was no mutation or deletion. The biological titer of produced mKate2 lentivirus was 1.6 × 10(6) TU/ml. At 96 hours after mKate2 lentivirus infection, fluorescence microscope showed that mKate2 was expressed in a large percentage of cells. FACS assay showed that the mKate2 positive rate was 93.8% ± 0.4%. Excitation light 530 ± 15 nm and emission light 710 ± 28 nm were the optimal imaging parameters for mKate2-HepG2 cells. CONCLUSION: Lentivirus can mediate efficiently the mKate2 reporter gene labeling of human liver cancer cell line HepG2. The mKate2-labeled HepG2 cells can be detected through in vitro fluorescence imaging. Further tracing studies of in vivo tumor fluorescence imaging are technically feasible.

Prospective versus retrospective ECG gating for 320-detector CT of the coronary arteries: comparison of image quality and patient radiation dose.

PURPOSE: To compare image quality and patient radiation dose in a group of patients who underwent 320-detector computed tomography coronary angiography performed with prospective electrocardiogram (ECG) gating with image quality and radiation dose in a group of patients matched for clinical features who underwent 320-detector computed tomographic (CT) coronary angiography performed with retrospective ECG gating. MATERIALS AND METHODS: This study was approved by our institutional human research committee. All patients had clinical indications for coronary computed tomography angiography (CTA). Two independent reviewers separately scored coronary artery segment image quality for 480 cardiac CT studies in prospective group and retrospective group (240 in each group). Reviewer variability was calculated. Estimated effective radiation dose was compared for prospective versus retrospective ECG gating. RESULTS: The two groups matched well for clinical characteristics and CT parameters. There was good agreement for coronary artery segment image quality scores between the independent reviewers (k=0.73). Of the 6408 coronary artery segments scored, there were no coronary artery segments that could not be evaluated in each group. Image quality scores were not significantly different (P>.05). Mean patient radiation dose was 76.50% lower for prospective gating (4.2 mSv) than for retrospective gating (18.1 mSv) (P<.01). CONCLUSION: Use of 320-detector CT coronary angiography performed with prospective ECG gating has similar subjective image quality scores but 76.50% lower patient radiation dose when compared with use of retrospective ECG gating.

[Construction and validation of dual fusion reporter gene expression vector for molecular imaging study].

OBJECTIVE: To construct dual fusion reporter gene expression vector containing enhanced green fluorescence protein (EGFP) and human transferrin receptor (TfR), and validate the reconstructed plasmid, which will provide experimental foundation for in vivo dual-modality optical/Magnetic Resonance (MR) imaging. METHODS: Clone TfR into the pEGFP-C1 vector to construct pEGFP-C1-TfR plasmid.pEGFP-C1-TfR plasmid was transfected into 293T cells for 48 h, then investigate EGFP expression under a fluorescence microscope; detect TfR expression through PT-PCR; inspect the subcellular location of EGFP-TfR fusion protein through Confocal Scanning Laser Microscopy; evaluate the function of EGFP-TfR fusion protein through Tf probe uptake and competition assays. RESULTS: DNA sequencing analysis confirmed that EGFP-TfR gene sequence was correct, and there was no mutation and deletion. After transfecting the reconstructed plasmid into 293T cells, fluorescence microscope observation and RT-PCR results demonstrated that EGFP and TfR were expressed efficiently. EGFP-TfR fusion protein was located predominantly in the cellular membrane, and could specifically mediate internalization of Tf. CONCLUSION: EGFP-TfR dual fusion reporter gene expression vector has been successfully constructed, and could be expressed efficiently with functional features. Thus, the expression vector could be applied for in vivo dual-modality optical/Magnetic Resonance (MR) imaging.

[Enhanced green fluorescence protein reporter gene labeling of mesenchymal stem cells mediated by lentivirus].

OBJECTIVE: To explore the effect of enhanced green fluorescence protein (EGFP) labeling mediated by lentivirus on the biophysical properties of mesenchymal stem cells (MSC), and whether the EGFP gene expression is permanent and stable. METHODS: MSC were infected with EGFP lentivirus at different virus multiplicity of infection (MOI). EGFP positive rate was measured with fluorescent-activated cell scanning (FACS) analysis, and EGFP expression in MSC was investigated under a fluorescence microscope. Cell viability, proliferation, apoptosis and cell cycle were detected with trypan blue stain, MTT colorimetric assay, Hoechst stain and FACS analysis respectively. To evaluate the stability of EGFP expression, EGFP lentivirus infected MSC were harvested after cultured continuously in vitro for 2, 4, 8 or 16 weeks, and EGFP positive rate and fluorescence strength were detected with FACS analysis. RESULTS: After infected with EGFP lentivirus (MOI = 20) for 96 h, EGFP positive rate of MSC was 97.39% +/- 0.68%. Cell viability, proliferation, apoptosis and cell cycle of MSC infected with EGFP lentivirus were unaffected, as compared with control MSC (P > 0.05). When cultured in vitro continuously for 2, 4, 8 or 16 weeks, EGFP positive rates of EGFP-MSC were 97.50% +/- 0.54%, 97.32% +/- 0.51%, 97.39% +/- 0.11%, and 97.48% +/- 0.13% respectively, while EGFP fluorescence strength were 440 +/- 13, 445 +/- 12, 458 +/- 13 and 456 +/- 16 respectively. Both EGFP positive rate and fluorescence strength kept in a stable level. CONCLUSION: EGFP lentivirus can efficiently label MSC and has no significant effect on the biophysical properties of MSC. EGFP gene expression in MSC is permanent and stable. EGFP-MSC can be used for further cell tracing research.

Chemoembolization with lobaplatin mixed with iodized oil for unresectable recurrent hepatocellular carcinoma after orthotopic liver transplantation.

PURPOSE: To determine whether chemoembolization can benefit patients with unresectable recurrent hepatocellular carcinoma (HCC) after orthotopic liver transplantation (OLT). MATERIALS AND METHODS: Twenty-eight of 71 patients (39%) with unresectable recurrent HCC following OLT and without contradictions to chemoembolization were included: 14 patients received chemoembolization after OLT (chemoembolization group) and 14 matched control subjects who did not receive chemoembolization (non-chemoembolization group). Tumor response was determined with follow-up computed tomography after each chemoembolization procedure and classified into four grades according to Response Evaluation Criteria in Solid Tumors. Overall survival was evaluated from OLT and from the diagnosis of recurrent HCC. RESULTS: Within a median follow-up of 14.5-months, 12 of the 14 patients in the chemoembolization group (86%) and 13 of the 14 in the non-chemoembolization group (93%) developed new recurrences. Eight of the 14 patients in the chemoembolization group (57%) showed partial tumor response (>30% reduction in the size of target lesions). Moreover, patients who underwent chemoembolization had a significantly longer overall survival after OLT (P = .0133) and after the diagnosis of HCC recurrence (P = .0338) compared to those who did not. No severe complications developed in patients receiving chemoembolization during follow-up. CONCLUSIONS: Lobaplatin-based chemoembolization may elicit effective tumor response for recurrent HCCs and improve the overall survival of patients with unresectable HCC recurrence following OLT.

MR tracking of magnetically labeled mesenchymal stem cells in rats with liver fibrosis.

PURPOSE: In vivo magnetic resonance (MR) tracking of magnetically labeled bone marrow mesenchymal stem cells (BMSCs) administered via the mesenteric vein to rats with liver fibrosis. MATERIALS AND METHODS: Rat BMSCs were labeled with superparamagnetic iron oxide (SPIO) and the characteristics of the BMSCs after labeling were investigated. Eighteen rats with CCL4-induced liver fibrosis were randomized to three groups to receive SPIO-labeled BMSCs (BMSC-labeled group), cell-free SPIO (SPIO group), or unlabeled BMSCs (control group). MR imaging of the liver was performed at different time points, and signal-to-noise ratio (SNR) of the liver was measured. In vivo distribution of delivered BMSCs was assessed by histological analysis. RESULTS: Labeling of BMSCs with SPIO did not significantly alter cell viability and proliferation activity. In BMSC-labeled group, the liver SNR immediately decreased from 8.56+/-0.26 to 3.53+/-0.41 at 1 h post injection and remained at a significantly lower level till 12 days (P<.05 versus the level before). By contrast, the liver SNR of the SPIO group almost recovered to the preinjection level (P=.125) at 3 days after a transient decrease. In control group, the liver SNR demonstrated no significant difference at the tested time points. Additionally, Prussian blue-positive cells were mainly distributed in the liver parenchyma, especially in injured areas. CONCLUSION: The magnetically labeled BMSCs infused through the mesenteric vein can be detected in the fibrotic liver of rats using in vivo MR imaging up to 12 days after injection.

[Clinical application of prospective electrocardiogram-gated 320-detector computed tomography coronary angiography].

OBJECTIVE: to compare the success rate, radiation dose, image quality and diagnosis of prospective electrocardiogram(ECG)-gated 320-detector computed tomography coronary angiography (CTCA) versus retrospective ECG-gated CTCA. METHODS: patients suspected coronary artery disease were divided into two groups which underwent 320-detector CTCA with prospective ECG-gated and retrospective ECG-gated scanning (n = 240 each, HR < 65 bpm). Curved-planar reconstruction (CPR), maximum intensity projection (MIP) and volume rendering (VR) were performed to demonstrate the coronary arteries. The image quality was defined as excellent, good and poor by motion and stair-step artifacts. Effective radiation exposure dose was estimated from the dose-length product. Effective radiation dose, image quality and diagnosis were evaluated. RESULTS: the success rate of examination was 100% in prospective ECG-gated group and retrospective ECG-gated group. The mean effective radiation dose of prospective ECG-gated CTCA [(3.3 ± 1.3) mSv] was significantly lower than that of retrospective ECG-gated CTCA [(13.0 ± 1.6) mSv, P < 0.01]. Segments of diagnostic image quality (95.42%, 3435/3600) and non-diagnostic coronary segments (4.58%, 165/3600) in prospective ECG-gated group were similar as those of retrospective ECG-gated group (95.81%, 3449/3600 and 4.19%, 151/3600, all P > 0.05). Compared with CAG, the sensitivity, specificity, false positive and false negative value in prospective ECG-gated group (93.22%, 99.21%, 91.64%, 99.05%) and retrospective ECG-gated group (94.55%, 98.80%, 95.86%, 98.54%) were not significantly different. CONCLUSION: though the effective radiation dose is significantly lower, the success rate, image quality and diagnosis of prospective ECG-gated 320-detector CTCA is comparable with that of retrospective ECG-gated 320-detector CTCA on patients with stable heart rates less than 65 bpm.

[Evaluation of esophageal varices and predicting the risk of esophageal varices bleeding with multi-detector CT in patients with portal hypertension].

OBJECTIVE: The objective of this study was to evaluate the performance of 320-row multi-detector CT (MDCT) in the detection and grading of esophageal varices and to evaluate the ability of MDCT in predicting the risk of hemorrhage in comparison with upper endoscopy in patients with portal hypertension. METHODS: A total of 69 patients, with clinically confirmed portal hypertension, underwent epigastric triphasic enhancement scans using 320-row MDCT 1 weeks or less before upper endoscopies were performed. Two blinded abdominal imagers retrospectively interpreted all CT images to detect the presence of esophageal varices and divided EV into large EV (≥ 5 mm) and small EV (< 5 mm). The correlation between CT measurements and endoscopic grading was assessed by kappa values. With endoscopy as standard, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of the two radiologists in detection of EV were calculated. Correlations between CT measurements of varix size and red color sign were assessed by correlation analysis. RESULTS: Of the total of 69 patients, 56 patients had esophageal varices, 41 had large EV, and 15 had small EV according to the endoscopic findings. MDCT showed an excellent interobserver reliability with regard to the diagnosis of the EV (k = 0.94). Agreement between CT and endoscopy with regard to the grading of EV were excellent (k = 0.77). The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of radiologist 1 in the detection of EV was 95%, 69%, 87%, 93% and 75% respectively; the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of radiologist 2 in the detection of EV was 93%, 77%, 87%, 95% and 71%, respectively. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of the two radiologists in the detection of large EV was 95%, 100%, 97%, 100% and 93%, respectively. CT variceal grading showed a strong correlation with endoscopic grading for both observers (P < 0.01). Correlations between CT measurements of varix size and red color sign were significant in both radiologists with a correlation coefficient r of 0.731 for radiologist 1 (P < 0.01) and 0.718 for radiologist 2 (P < 0.01). CONCLUSION: 320-row MDCT is useful for the detection and grading of EV, and it is useful in evaluation of EV for predicting a risk of hemorrhage.

Selection of the most powerful predictors for the evaluation of hepatic steatosis grade: an experimental study.

PURPOSE: To select the most powerful predictors for the evaluation of hepatic steatosis grade. METHODS AND MATERIALS: Forty-five healthy New Zealand rabbits were randomly divided into one normal control group and three experimental groups. Hepatic steatosis models were established by feeding a high-fat, high-sugar diet and drinking water containing 5% ethanol. Twenty-two variable indexes were measured using general observation, biochemical examination, ultrasonography, computed tomography (CT), and proton magnetic resonance spectroscopy (MRS). Univariate analysis, correlation analysis, and stepwise regression analysis were used to make the selection of the most powerful predictors. ROC analysis was used to compare the diagnostic efficacy of single index with combined index (Y) expressed by a regression equation. RESULTS: Based on statistical analysis, there were 12 variable indexes with significant differences among groups, which correlated with hepatic steatosis grade: liver weight, hepatic index, liver CT value, liver-to-muscle attenuation ratio, 1H MRS fat peak value, fat peak area, fat-to-water peak area ratio, fat percentage, ultrasound attenuation coefficient, serum aspartate aminotransferase, total cholesterol (TC) and triglycerides. Among them hepatic index, liver CT value and serum TC were selected as the most powerful predictors for hepatic steatosis grade with correlation coefficients of 0.709, -0.764, and 0.886, respectively. The regression equation was: Y=1.975 + 3.906 x 10(-2)X1 + 0.369X2-2.84 x 10(-2)X3, where Y=hepatic steatosis grade, X1=TC, X2=hepatic index, and X3=liver CT value. ROC analysis displayed PPV, NPV, curve area of combined index (Y) were superior to simple index (hepatic index, liver CT value and serum TC) in evaluating hepatic steatosis grade, and they were nearly 1.0000, 1.0000 and 1.000, respectively. CONCLUSIONS: Combined application of several diagnostic methods is superior to simple diagnostic method, and could provide comprehensive, rapid, accurate evaluation of hepatic steatosis grade.

[The role of early hepatic artery ischemia on biliary complications after liver transplantation and hepatic arterial interventional therapy].

OBJECTIVE: To explore the influence of early hepatic artery ischemia on the occurrence and prognosis of biliary complications after orthotopic liver transplantation (OLT), and the value of early hepatic arterial interventional therapy. METHODS: In the 720 recipients who received OLT in our hospital from October 2003 to June 2007, 32 cases were detected hepatic artery stenosis (HAS, 30 cases) or hepatic artery thrombosis (HAT, 2 cases) by color Doppler Ultrasound from 4 to 65 days (mean, 25 +/- 15) after OLT. All of them were confirmed by DSA and/or CT angiography. Of the 32 patients, 20 were treated by hepatic arterial interventional therapy. The end-point of follow-up was the time of patient's death and retransplantation. RESULTS: In this study, 20 cases developed biliary complications, including the common bile duct stenosis in 2 cases, intra- and extra hepatic bile duct stenosis in 13 cases and multiple intrahepatic bile duct stenosis in 5 cases. Among them, 2 patients complicated with bile leakage, 4 with biloma and 3 with liver abscess. Of the 20 patients, 8 with HAS received successful hepatic arterial interventional therapy which was performed two weeks after HAS detected; 10 with HAS didn't receive hepatic arterial interventional therapy; 1 with HAT received successful thrombolysis; 1 with HAS received failed hepatic artery stent implantation. During a median follow-up of 262 days (range, 22 -517 days), 10 patients died, 6 underwent retransplantation, and the other 4 survived; cumulated survival rates at 6, 12 and 24 months were 60.0%, 34.9% and 0, respectively. 12 cases didn't develop biliary complications. Nine of them received successful hepatic arterial interventional therapy within 2 weeks HAS detected, 2 with acute rejection received flushing anti-rejection therapy, 1 with HAT received retransplantation because of unsuccessful thrombolysis. During a median follow-up of 952 days (range, 14 - 1398 days), 3 patients died, 1 underwent retransplantation, and the other 8 survived; cumulated survival rates at 6, 12 and 24 months were 75%, 66.7% and 66.7%, respectively. CONCLUSION: Early hepatic artery ischemia after OLT is an important agent for biliary complications. Early and successful hepatic arterial interventional therapy helped to reduce the incidence of biliary complications and improve the patients' prognosis.