Zi-Ping Li

Systematic review with meta-analysis: magnetic resonance enterography vs. computed tomography enterography for evaluating disease activity in small bowel Crohn's disease.

Magnetic resonance enterography (MRE) has been proposed as a non‐ionising alternative method to computed tomography enterography (CTE). Some studies have directly compared CTE and MRE in patients with small bowel Crohns disease (CD) with variable results.

Fecal calprotectin for evaluating postoperative recurrence of Crohn's disease: a meta-analysis of prospective studies.

Background:Fecal calprotectin (FC) levels have been extensively reported to correlate with clinical and endoscopic activities in Crohns disease (CD); however, the utility of FC levels in the postoperative setting remains to be determined. Using meta-analysis, we aimed to evaluate the utility of FC as a noninvasive marker of recurrence in patients with CD who had undergone previous surgical resection. Methods:An electronic search using keywords related to CD and FC was performed in multiple electronic resources from 1966 to March 2014. The extracted data were pooled using a hierarchical summary receiver operating curve model. Results:Ten articles met the inclusion criteria, and methodological quality was determined in detail for each study. The 10 studies presented FC levels in 613 postoperative CD patients. The pooled sensitivity and specificity values for assessing suspected endoscopic recurrence were 0.82 (95% confidence interval (CI), 0.73–0.89, 8 studies, n = 391) and 0.61 (95% CI, 0.51–0.71), respectively. The overall positive and negative likelihood ratios were 2.11 (95% CI, 1.68–2.66) and 0.29 (95% CI, 0.197–0.44), respectively. The pooled sensitivity and specificity values for evaluating clinical relapse were 0.59 (95% CI, 0.47–0.71; 3 studies, n = 183) and 0.88 (95% CI, 0.80–0.93), respectively. The overall positive and negative likelihood ratios were 5.10 and 0.47, respectively. Conclusions:As a simple and noninvasive marker, FC is useful in evaluating recurrence of postoperative patients with CD.

CT Enterography in Evaluating Postoperative Recurrence of Crohn's Disease after Ileocolic Resection: Complementary Role to Endoscopy.

Background:Ileocolonoscopy is the gold standard to assess postoperative recurrence (POR) in patients with Crohn’s disease (CD) who have undergone ileocolic resection. Although computed tomographic enterography (CTE) yields striking findings in the small bowel of CD, its role in POR is undefined. The aim of this study was to compare ileocolonoscopy and CTE for evaluating POR in CD. Methods:The analysis included 32 patients with CD with ileocolic resection. Ileocolonoscopy and CTE were performed within 1 week. Endoscopic recurrence was defined using Rutgeerts score (i0–i4), whereas CTE recurrence was assessed according to a previously validated CTE score (CTE0–CTE3). Patients were followed up for a maximum of 30 months, and the primary endpoint was reoperation. Results:There was a good correlation between endoscopic and CTE recurrence (r = 0.782, P < 0.0001). Moreover, CTE identified the presence of jejunal and proximal ileum disease (n = 7), fistula (n = 3), and abscess (n = 4). Therapeutic management was thereby modified in 8 of 32 patients (25.0%). Eleven patients received major reoperation. There was no significant difference regarding the rate of reoperation between subgroups Rutgeerts score i3–4 and i0–2 (P > 0.05), whereas there was significant difference between subgroups’ CTE2–CTE3 and CTE0–CTE1 (P < 0.05). Conclusions:CTE is a reliable method in assessing POR in patients with CD who have undergone ileocolic resection. CTE may serve as an important complementary tool to endoscopy for evaluation of the postoperative course of CD.

Pancreatic neuroendocrine tumours: correlation between MSCT features and pathological classification.

ObjectivesWe aimed to evaluate the multi-slice computed tomography (MSCT) features of pancreatic neuroendocrine neoplasms (P-NENs) and analyse the correlation between the MSCT features and pathological classification of P-NENs.MethodsForty-one patients, preoperatively investigated by MSCT and subsequently operated on with a histological diagnosis of P-NENs, were included. Various MSCT features of the primary tumour, lymph node, and distant metastasis were analysed. The relationship between MSCT features and pathologic classification of P-NENs was analysed with univariate and multivariate models.ResultsContrast-enhanced images showed significant differences among the three grades of tumours in the absolute enhancement (Pu2009=u20090.013) and relative enhancement (Pu2009=u20090.025) at the arterial phase. Univariate analysis revealed statistically significant differences among the tumours of different grades (based on World Health Organization [WHO] 2010 classification) in tumour size (Pu2009=u20090.001), tumour contour (Pu2009<u20090.001), cystic necrosis (Pu2009=u20090.001), tumour boundary (Pu2009=u20090.003), dilatation of the main pancreatic duct (Pu2009=u20090.001), peripancreatic tissue or vascular invasion (Pu2009<u20090.001), lymphadenopathy (Pu2009=u20090.011), and distant metastasis (Pu2009=u20090.012). Multivariate analysis suggested that only peripancreatic tissue or vascular invasion (HR 3.934, 95xa0% CI, 0.426–7.442, Pu2009=u20090.028) was significantly associated with WHO 2010 pathological classification.ConclusionsMSCT is helpful in evaluating the pathological classification of P-NENs.Key Points• P-NENs are potentially malignant, and classification of P-NENs carries important prognostic value.• MSCT plays an important role in the diagnosis and staging of P-NENs.• Correlations between classification of P-NENs and imaging findings have not been systematically evaluated.• MSCT could predict P-NENs classification and may be a useful prognostication tool.

pH-Sensitive Nanomicelles for Controlled and Efficient Drug Delivery to Human Colorectal Carcinoma LoVo Cells

Background The triblock copolymers PEG-P(Asp-DIP)-P(Lys-Ca) (PEALCa) of polyethylene glycol (PEG), poly(N-(N’,N’-diisopropylaminoethyl) aspartamide) (P(Asp-DIP)), and poly (lysine-cholic acid) (P(Lys-Ca)) were synthesized as a pH-sensitive drug delivery system. In neutral aqueous environment such as physiological environment, PEALCa can self-assemble into stable vesicles with a size around 50-60 nm, avoid uptake by the reticuloendothelial system (RES), and encase the drug in the core. However, the PEALCa micelles disassemble and release drug rapidly in acidic environment that resembles lysosomal compartments. Methodology/Principal Findings The anticancer drug Paclitaxel (PTX) and hydrophilic superparamagnetic iron oxide (SPIO) were encapsulated inside the core of the PEALCa micelles and used for potential cancer therapy. Drug release study revealed that PTX in the micelles was released faster at pH 5.0 than at pH 7.4. Cell culture studies showed that the PTX-SPIO-PEALCa micelle was effectively internalized by human colon carcinoma cell line (LoVo cells), and PTX could be embedded inside lysosomal compartments. Moreover, the human colorectal carcinoma (CRC) LoVo cells delivery effect was verified in vivo by magnetic resonance imaging (MRI) and histology analysis. Consequently effective suppression of CRC LoVo cell growth was evaluated. Conclusions/Significance These results indicated that the PTX-SPION-loaded pH-sensitive micelles were a promising MRI-visible drug release system for colorectal cancer therapy.

MR Quantification of Total Liver Fat in Patients with Impaired Glucose Tolerance and Healthy Subjects

Objective To explore the correlations between liver fat content and clinical index in patients with impaired glucose tolerance (IGT) and healthy subjects. Materials and Methods 56 subjects were enrolled and each of them underwent upper-abdominal MRI examination that involved a T1 VIBE Dixon sequence. 14 was clinically diagnosed with IGT (collectively as IGT group ) while 42 showed normal glucose tolerance,(collectively as NGT group). NGT group was further divided into NGTFat (BMI≥25, 18 subjects) and NGTLean (BMI<25, 24 subjects). The total liver fat contents was measured and compared with clinical findings and laboratory results in order to determine statistical correlations between these parameters. Differences among IGT, NGTFat and NGTLean groups were evaluated. Results For all the subjects, fat volume fractions (FVFs) ranged from 4.2% to 24.2%, positive correlations was observed with BMI, waist hip ratio(WHR), low density lipoprotein(LDL), fasting plasma insulin(FPI), homeostasis model assessment insulin resistance (HOMA-IR) and homeostasis model assessment β(HOMAβ). FVFs of IGT group (pu200a=u200a0.004) and NGTFat group (pu200a=u200a0.006) were significantly higher than those of NGTLean group. Conclusions People with higher BMI, WHR and LDL levels tend to have higher liver fat content. Patients with BMI≥25 are more likely to develop IGT. Patients with higher FVF showed higher resistance to insulin, thus obtained a higher risk of developing type 2 diabetes mellitus.

Functional magnetic resonance cholangiography enhanced with Gd-EOB-DTPA: Effect of liver function on biliary system visualization

To evaluate effect of liver function on biliary system visualization using gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd‐EOB‐DTPA)‐enhanced magnetic resonance cholangiography (CE‐MRC).

CT Evaluation of Gastroenteric Neuroendocrine Tumors: Relationship Between CT Features and the Pathologic Classification

OBJECTIVEnThe objective of our study was to compare the CT features of gastroenteric neuroendocrine neoplasms (GE-NENs) with the pathologic classification and to analyze the correlation between the CT features and classification of GE-NENs.nnnMATERIALS AND METHODSnFifty-six cases of pathologically and immunohisto-chemically proven GE-NENs, including 25 cases of neuroendocrine tumors (NETs) (i.e., G1 and G2 tumors) and 31 cases of neuroendocrine carcinomas (NECs) (i.e., G3 tumors and mixed adenoneuroendocrine carcinomas) were studied. We analyzed various CT features of the primary tumor, nodal status, and metastasis and compared these features with pathologic grading.nnnRESULTSnThe CT features that favor NEC over NET include larger tumor size (> 4.0 cm), transmural invasion, circumscribed tumor with both intra- and extraluminal involvement, circumferential growth, areas of cystic change or necrosis, ulceration, mesenteric fat infiltration, and lymphadenopathy, with p values of 0.044, 0.002, 0.024, 0.008, 0.002, 0.007, 0.002, and < 0.001, respectively. The CT features that do not distinguish between the two types of GE-NENs include tumor boundary, growth pattern, degree of enhancement, adjacent organ invasion, distant organ metastasis, and peritoneal seeding, with p values of 0.277, 0.153, 0.672, 1.000, 0.159, and 0.877, respectively.nnnCONCLUSIONnCT can be useful in the classification of GE-NENs.

Nanoparticles for Colorectal Cancer Targeted Drug Delivery and MR Imaging: Current Situation and Perspectives.

The application of nanoparticles (NPs) offers new prospects for the early detection and effective therapy of colorectal cancer (CRC). Various NPs have been designed and explored as diagnostic and/or therapeutic drug delivery vehicles. To achieve selective treatment and to reduce toxicity, these nanoparticles are usually endowed with targeting abilities. Passive targeting is based on the extravasation and enhanced permeability and retention effect of tumors, while active targeting always involves binding to specific ligands that are recognizable by CRC tissues, such as vascular endothelial growth factor, folate, monoclonal antibodies (mAbs), aptamers, and membrane penetrating peptides. In addition, contrast agents, such as gadolinium complexes and iron oxide particles, can be introduced into the delivery system to enable MR imaging and lesion detection. Furthermore, smart carriers have been gradually applied to the delivery system. These carriers are designed to respond to certain changes in the bio-environment and release encapsulated contents on demand, thus achieving effective drug concentrations at tumor sites. This review focuses on recent advances of NP technology for the targeted diagnosis and treatment of CRC and aims to unveil the emerging possibilities of using nanocarriers to enhance therapeutic applications.

Molecular Targeted Magnetic Resonance Imaging of Human Colorectal Carcinoma (LoVo) Cells Using Novel Superparamagnetic Iron Oxide- Loaded Nanovesicles: In Vitro and in vivo Studies

OBJECTIVEnTo investigate the feasibility of superparamagnetic iron oxide (SPIO) nanoparticles (SPIO) as a magnetic resonance (MR) contrast agent to enhance tumor imaging in vivo.nnnMETHODSnHydrophobic SPIO (oil-soluble SPIO; OSPIO) and hydrophilic SPIO (water-soluble SPIO; WSPIO) were loaded in methoxy-poly(ethylene glycol)-block-poly(D,L-lactic acid) (PEG-PDLLA) nanovesicles. Three groups of nude mice (n=12/group) xenografted with human colorectal carcinoma (LoVo) cells were injected into the caudal vein with WSPIO, OSPIO-loaded nanovesicles, or WSPIO-loaded nanovesicles. MRI scans were performed on all of the mice, and the relative T2 values were measured in the tumor and the liver. The differences in these T2 values between the three groups were compared.nnnRESULTSnThe peak relative T2 values in the tumors detected by the OSPIO- or WSPIO-loaded contrast agents were reduced by 10.12% and 11.40%, respectively. The relative T2 values in the WSPIO- and OSPIO-loaded polymeric nanovesicle groups were more pronounced than the relative T2 value in the WSPIO group (P<0.05), but there was no significant difference in the T2 value between the OSPIO- and WSPIO-loaded vesicle groups (P＞0.05). The greatest T2 value decreases in the liver in the WSPIO, OSPIO-loaded and WSPIO-loaded vesicle groups were 32.85%, 52.77% and 56.89%, respectively. The decrease in the T2 values was more pronounced in the WSPIO- and OSPIO-loaded nanovesicle groups than in the WSPIO group (P<0.05) and was more apparent in the WSPIO-loaded nanovesicle group than in the OSPIO-loaded nanovesicle group (P<0.05).nnnCONCLUSIONnSPIO-loaded polymeric nanovesicles generate significant T2WI signal intensity decreases in vivo and are anticipated to be used as novel and effective contrast agents for tumor imaging.