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Objective: To investigate whether fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) combined with thin-section CT improves the diagnostic performance for solitary pulmonary nodules (SPNs)., Methods: A total of 267 patients underwent examinations with 18 F-FDG PET/CT and thin-section CT for evaluating the SPNs with undetermined nature, which was further confirmed by pathological examination or clinical follow-up. The performance of two diagnostic criteria based on findings in PET/CT alone (Criterion 1) and in PET/CT combined with thin-section CT (Criterion 2) were compared., Results: Thin-section CT provided greater diagnostic information for SPNs in 84.2% of the patients. Compared with Criterion 1, the diagnosis based on Criterion 2 significantly increased the diagnostic sensitivity (80.4% vs 91%, P<0.01) and accuracy (76.4% vs 87.2%, P<0.01) for lung cancer. The lesion size and the CT features including lobulation, air bronchogram, and feeding vessel, but not SUVmax, were all helpful for characterizing non-solid SPNs. Thin-section CT rectified diagnostic errors in 50% (20/40) of the cancerous lesions, which had been diagnosed as benign by PET due to their low metabolism. For non-solid SPNs, Criterion 2 showed a significantly higher diagnostic sensitivity than Criterion 1 (90.0% vs 40.0%, P=0.000) but their diagnostic specificity were comparable (75.2% vs 58.3%, P=0.667). For solid nodules, the use of thin-section CT resulted in no significant improvement in the diagnostic performance (P<0.05)., Conclusion: The combination of PET/CT and thin-section CT creates a synergistic effect for the characterization of SPNs, especially non-solid nodules.

Objective: The co-occurrence of blue rubber bleb nevus syndrome (BRBNS) and ventricular septal defects is rare. Here we present a case of BRBNS in a 15-year-old boy who was born with multiple cavernous hemangiomas and a ventricular septal defect. Examinations revealed the presence of hemangioma lesions in the subcutaneous and mucosal tissues as well as in the cerebrum, nasopharynx, tongue, esophagus, gastric body, sigmoid colon and adrenal gland. Combined imaging modalities played an important role in the diagnosis of hemangioma lesions.

Objective: To investigate the characteristic 18 F-FDG PET/CT findings in patients with primary intestinal lymphoma (PIL)., Methods: We collected the clinical and 18 F-FDG PET/CT data of 23 patients with PIL who underwent 18 F-FDG PET/CT in our center between January, 2005 and January, 2016. The location, morphologies and metabolic features of the lesions were analyzed in these patients., Results: In the 23 PIL patients, diffusive large B cell lymphoma (DLBCL) and enteropathy- associated T cell lymphoma (EATL) were the primary histopathological types, accounting for 47.8% and 43.4% of the total patients, respectively. The ileum, ileocecus and ascending colon were the most commonly compromised locations (57.0%). All the 42 intestinal lesions showed 18 F-FDG-avid foci with a mean SUVmax of 15.2∓8.1 (range 3.6-33.7), and no significant difference was found in SUVmax between DLBCL and EATL groups (t=1.851, P=0.073). Diffusive regular or irregular intestinal wall thickening was the primary CT finding in PIL lesions without significant difference between the two groups (χ 2 =0.426, P=0.514). The aneurismal sign was found in 26.2% (11/42) lesions, more commonly seen in the patients with DLBCL than in those with EATL (χ 2 =8.101, P=0.004). PET/CT detected abdominal lymph node involvement of lymphoma was detected in 56.5% of the patients, and a small quantity of asites was seen in 30.4% of the patients., Conclusion: PIL presents with characteristic imaging features in 18 F-FDG PET/CT. 18 F-FDG PET/CT is a sensitive imaging modality for detecting inter- and extra-intestinal lesions of PIL and displays characteristic imaging features of the disease.

Objective: To explore the computed tomography (CT) and magnetic resonance imaging (MRI) features of desmoid-type fibromatosis, and improve the diagnostic accuracy and understanding of the disease., Methods: The CT and MRI features of 18 cases of surgically and pathologically confirmed desmoid-type fibromatosis were reviewed retrospectively. Among the patients, 10 received CT pre- and post-contrast scanning, and 8 patients had MRI pre- and post-contrast scanning. The CT and MRI features were analyzed in comparison with the pathological findings., Results: In the extra abdominal cases, the tumors occurred in the head and neck in 3, in the dorsal part of the chest in 2, in the abdominal wall and groin area in 9, and in the peritoneal cavity in 4; concomitant Gardner syndrome was found in 1 case. In 4 cases the tumor occurred within 1 to 3 years after abdominal surgeries. Pathologically, the lesion was hard and composed of fusiform fibroblasts and myofibroblast. The cells showed no obvious heteromorphism with few karyokinesis, growing invasively and recurrent locally but without distant metastasis. Immunohistochemically, the fibroblasts and myofibroblasts expressed vimentin, and the myofibroblasts were positive for SMA. On CT and MRI, the lesion appeared benign with malignant growth pattern, and caused compression of the adjacent organs and vessels or encasement of the vessels; the border was unclear without encapsulation, and necrosis and calcification was scarce. The density and signal of the tumor were well distributed. Twelve patients displayed obvious enhancement and 5 showed uneven enhancement., Conclusion: The CT and MRI features of desmoid-type fibromatosis are characteristic, and CT and MRI are valuable modalities for the diagnosis and differential diagnosis of the tumor.

Objective: To investigate the alteration of apparent diffusion coefficient (ADC) in diffusion-weighted MR imaging (MR-DWI) of liver fibrosis and its pathological basis in rabbits., Methods: Five rabbits in the control group and 22 with experimental liver fibrosis induced by transperitoneal injection of carbon tetrachloride (CCl4) were examined with MR-DWI. Diffusion-weighted SE EPI sequence with a relatively high b factor (b=600 s/mm2) was used to measure the ADC. The mean values of ADC were compared among the rabbits in different stages of liver fibrosis and analyzed in relation to the pathological findings., Results: The mean ADC value decreased significantly with increased severity of liver fibrosis (P<0.05). Pathologically, the amount and extension of fibrotic matrix increased, and the hepatic necroinflammation worsened with the progression of the liver fibrosis., Conclusion: The ADC value decreases with the progression of liver fibrosis possibly as the result of water diffusion limitation due to increased fibrous tissue in the liver and abnormal water diffusion within the intracellular and extracellular spaces.

Objective: To assess the value of (18)F-fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography ((18)F-FDG PET-CT) in ultrasound-guided local ablation of malignant liver tumors., Methods: Thirteen patients with 35 local residual tumor foci following previous tumor ablation underwent (18)F-FDG PET-CT and ultrasound-guided local ablation with intratumoral alcohol injection., Results: After the second local ablation guided by (18)F-FDG PET-CT and ultrasound, radioactive defects were detected in the corresponding location in 31 of the 35 residual foci, and after the third local ablation, the other 4 foci also showed radioactive defects., Conclusion: (18)F-FDG PET-CT can sensitively and accurately identify tissue necrosis and residual tumors, and serves as an excellent approach for ultrasound-guided local ablation of local residual tumors.

Objective: To investigate the effect of rabbit saphenous and sciatic nerve homogenates on the proliferation and calcification of rabbit osteoblasts in vitro., Method: The saphenous nerves (sensory nerves) and the muscular branches of the sciatic nerve (motor nerve) were collected from 48 New Zealand white rabbits to prepare the nerve tissue homogenates. Bone marrow mesenchymal stem cells (MSCs) were isolated from the rabbits and cultured in vitro, and after 14 days of routine osteogenic induction, the resultant osteoblasts were identified by immunohistochemistry, alkaline phosphatase (ALP) and Alizarin red S staining. The osteoblasts were then incubated in the induction medium containing the saphenous (sensory nerve group) or sciatic homogenates (motor nerve group), with the cells in the dexamethasone-containing, dexamethasone-free osteogenic induction medium and control medium as the control. The proliferation, total protein and ALP activity of the osteoblasts were measured every other day until the 8th day, and Alizarin red S staining was used for quantitative analysis of calcification of the cells after two weeks., Results: The application of the saphenous nerve homogenates significantly promoted cell proliferation, total protein and ALP activity (P<0.01, P<0.05 and P<0.05), while exposure of the osteoblasts to dexamethasone inhibited the cell proliferation (P<0.001). Compared to dexamethasone-free group, the saphenous homogenates enhanced the mineralization of the osteoblasts (P<0.001)., Conclusion: Saphenous nerve homogenates significantly promotes the proliferation, differentiation, ALP activity and mineralization of rabbit osteoblasts, but sciatic nerve homogenates do not show osteogenic effects on the cells.

Objective: To construct a recombinant retroviral vector for RNA interference targeting human telomerase reverse transcriptase (hTERT)., Methods: The sequences coding for enhanced fluorescence protein (EGFP), U6 promoter and a small interfering RNA (siRNA) targeting hTERT were amplified by PCR, respectively, and sub-cloned sequentially into the retroviral shuttle plasmid pLXSN to construct the plasmid pLXSN-EGFP-U6-siTERT. The recombinant expression plasmid was identified by restriction enzyme digestion and sequencing. Fluorescence microscopy and flow cytometry were employed to analyze EGFP expression in NIH3T3 transfected with the recombinant plasmid, and MMT assay was performed to evaluate the growth inhibition of Hela cells resulting from RNA interference mediated by the plasmid., Results: Sequence analysis and restriction enzyme digestion showed that the recombinant expression plasmid pLXSN-EGFP-U6-siTERT was constructed successfully. Twenty-four hours after transfection of NIH3T3 cells with the recombinant plasmid, the expression rate of EGFP reached 24.1% as shown by flow cytometry. MTT assay demonstrated a cell death rate of 53.2% 72 h after transfection of Hela cells with the plasmid., Conclusion: The successful construction of the recombinant retroviral plasmid mediating potent cell growth inhibition suggests the great potential of RNA interference technique in suppressing hTERT expression in mammalian tumor cells.

Objective: To assess the clinical value of fluorine-18-2-fluoro-2-deoxy-D-glucose ((18)F-FDG) positron-emission tomography/computed tomography (PET/CT) in preoperative evaluation of hepatocellular carcinoma (HCC) patients for liver transplantation and in early detection of recurrent foci after the operation., Methods: A retrospective study was conducted involving 19 HCC patients undergoing (18)F-FDG PET/CT before and after liver transplantation. The pre- and postoperative clinical data and (18)F-FDG PET/CT images of these patients were analyzed. Totally 10 (18)F-FDG PET/CT examinations (in 8 patients) were performed for purpose of preoperative evaluation of the transplantation and assessment of the tumor elimination and general metastasis following the adjuvant therapy, and 22 examinations (in 11 patients) performed postoperatively to identify recurrent foci and metastasis. The average time span between (18)F-FDG PET/CT examination and the operations was 8.68 months., Results: PET examinations in 2 patients for preoperative evaluations showed no evidence of tumor recurrence or metastasis, so they underwent liver transplantation as scheduled. (18)F-FDG PET/CT found distinct metastasis in the target operation area in another 2 patients, and liver transplantation was performed with proper management of the metastatic foci. The other 4 patients were found to have distal metastasis, so that operations were cancelled and the patients received interventional therapy and other treatments instead. Postoperative (18)F-FDG PET/CT examination discovered no metastatic foci in 2 patients, but detected mycotic brain abscess in 1 patient. Another 19 postoperative (18)F-FDG PET/CT examinations (in 8 patients) showed recurrence in the grafted liver (in 4 patients), tumor embolism in the left and right hepatic veins and in the inferior vena cava, in addition to metastasis to the lungs, lymph nodes, bone, spleen, parietal pleura, intervertebral foramen of the thoracic vertebra etc., Conclusion: (18)F-FDG PET/CT scanning shows superior accuracy in identification of lymph node tumor metastasis. With the advantages of whole-body scanning and high sensitivity of tumor detection, (18)F-FDG PET/CT can be instrumental in preoperative evaluation of liver transplantation for HCC (such as modification of the clinical staging) and postoperative early detection of recurrent tumors.