Advances in the construction of a scaffold for cardiac tissue engineering containing homogeneous and stable carbon nanotubes / 中国组织工程研究

BACKGROUND: How to efficiently and uniformly disperse carbon nanotubes (CNTs) into a tissue-engineered scaffold is crucial to construct an ideal CNTs-Polymer composite scaffold and it is also a hotspot of research in the tissue engineering. OBJECTIVE: To review the advances in the methodology progress of constructing a scaffold for cardiac tissue engineering, which contains uniformly and stably dispersed CNTs. METHODS: The Web of Science Core Collection and PubMed were searched by the first author for related papers about CNTs dispersion in the cardiac tissue engineering published from October 2004 to January 2017. The key words were "carbon nanotubes, dispersion, cardiac tissue engineering" in English. Original research papers were searched, which were screened through titles, abstracts and contents, and then reviewed. RESULTS AND CONCLUSION: CNTs are easy to aggregate because of high surface area, high aspect ratio and rough surface. Thus, it is one of the key points to construct an ideal CNTs-Polymer composite scaffold that whether CNTs could be uniformly and stably dispersed in polymer scaffolds. In the cardiac tissue engineering, covalent or non-covalent surface modification of CNTs significantly enhances the uniformity and stability of CNTs in the polymer scaffolds, which is conducive to construct the uniformly and stably CNTs-dispersed scaffold for cardiac tissue engineering, leading to notable improvement in mechanical and electrical properties of engineered cardiac tissues.

Diagnostic methods for initial evaluation of primary gastrointestinal stromal tumors

To describe the imaging features of gastrointestinal stromal tumors [GISTs] at initial presentation with clinical, surgical, and pathologic correlation, and to evaluate values of various techniques in GISTs. This retrospective study recruited 70 patients with histologically proved GISTs between December 2004, and May 2009 in the Department of General Surgery, Zhongshan Hospital, Fudan Univeristy, Shanghai, China. Each patient underwent CT scanning, 39 patients underwent simultaneous endoscopy, 12 patients underwent endoscopic ultrasound [EUS], and 36 patients underwent transabdominal ultrasonography [TAUS] simultaneously. Features of GISTs were assessed. Computerized tomography findings showed an eccentric mass in 44 patients, an intraluminal component in 24, and a transmural distribution in 2. Forty-two tumors were dumbbell-shaped, 2 were round, while 26 were irregular. Forty-three tumors presented with well-defined masses, while 27 with unclear borders. The arterial phase attenuation showed the continuous enhancement. The portal-venous phase attenuation was heterogeneous in 26 and homogeneous in the other 44. There was a significant correlation between certain CT features and tumor risk stratification. Gastrointestinal stromal tumors were characterized by a smooth shape and normal overlying mucosa in endoscopy, hypoechoic, and solid in TAUS. Imaging examinations are pivotal in the management of GISTs. The CT scan is valuable in the diagnosis, staging, and treatment planning of GISTs. Endoscopy and EUS contribute to the detection of mucosal lesions. Other methods including TAUS, fluorodeoxyglucose positron emission tomography, CT gastrography, and MRI help in specific cases

The comparative study of the imaging features of chromophobe cell renal carcinoma with pathologic findings / 中华放射学杂志

Objective To analyze and compare the imaging features of chromophobe cell renal carcinoma(CCRC)with pathologic findings in order to improve the diagnostic accuracy.Methods The data of CT and MRI of 12 patients with CCRC were reviewed retrospectively.Ten patients underwent CT examination,including precontrast scan,the contrast eortieomedullary phase scan and the parenchymal phase scan(one patient without corticomedullary phase scan).Two patients underwent MR examination including precontrast T_1WI,T_2WI and enhanced T_1WI of the corticomedullary phase and the parenchymal phase.Results Four lesions located in left kidney and eight in right kidney.Maximum diameter of lesions ranged from 24 mm to 125 mm,average 56.7 ram.Homogenous density was observed in six lesions of ten on unenhanced CT scan and five lesions had homogenous enhancement on enhanced CT scan,which was due to the less incidence of necrosis,liquefaction and hemorrhage on pathologic findings.Nine Lesions showed hyperdense compared with renal medulla but the density was lower than renal cortex on the corticomedullary phase.The enhanced degree was positively correlated with microvessel density(MVD).All ten lesions became hypodense compared with renal medulla on the parenchymal phase scan.Central stellate scar was found in two big lesions and psudocapsula were observed in four lesions confirmed by pathology.Two patients underwent MRI examination.Compared with medulla,the two lesions showed hyperintense on unenhanced T_1WI and obviously hypointense on unenhaneed T_2WI.The enhancement pattern of them was similar to CT. Conclusion The imaging features of CCRC,such as homogeneity,special enhancement pattern and distinct hypointensity on T_2WI,help to differentiate CCRC from other renal tumors.

The comparative study of diffusion-weighted MR imaging with modified sensitivity encoding technique for small hepatocellular carcinoma lesions / 中华放射学杂志

Objective To prospectively evaluate whether DWI with mSENSE(mSENSE-DW1)can help to improve image quality and affect the calculation of lesion's ADC,compared with DWI with conventional phase encoding(conventional DWI)in patients with small HCC lesions.Methods Thirty-two patients with 47 small HCC lesions underwent single-shot spin-echo echo-planar.(SE-EPI)DWI with conventional phase encoding and mSENSE.Three b values of 300,500 and 800 s/mm~2 were used.Image quality and CNR between conventional DWI and mSENSE-DWI group were compared with different b value. Lesion's ADC were also calculated and compared.Matched-pairs Wilcoxon signed rank test and Friedman test were used to test statistical significance.Results The image quality was assessed with a five-point scale.For conventional DWI group,image quality score of 2 was assigned in 5 cases,score of 3 in 24 cases, score of 4 in remaining 3 eases with b=300 s/mm~2,score of 2 in 9 eases,score of 3 in 22 cases,score of 4 in remainingl cases with b=500 s/mm~2,score of 1 in 2 cases,score of 2 in 24 cases,score of 3 in remaining 6 cases with b=800 s/mm~2.For mSENSE-DWI group,image quality score of 3 was assigned in 4 cases,score of 4 in 25 cases,score of 5 in 3 eases with b=300 s/mm~2,score of 3 in 10 cases,score of 4 in 20 cases,score of 5 in remaining 2 cases with b=500 s/mm~2,score of 2 in 7 cases,score of 3 in 23 eases, score of 4 in remaining 2 cases with b=800 s/mm~2.Higher image quality scores were achieved at mSENSE- DWI group than conventional DWI group(Z=-5.578,-5.488,-4.796 respectively,P

CT findings of primary adrenocortical carcinoma / 中华放射学杂志

Objective To explore the imaging features and dynamic CT findings of primary adrenocortical carcinoma and evaluating its clinical value.Methods All 11 cases patients with primary adrenocortical carcinoma confirmed by surgical pathology underwent spiral CT plain scanning and two phases dynamic enhancement scanning before operation.Contrast injection was done by using nonionic Omnipaque at a flow rate of 3 ml/s with a power injector.The CT images were reviewed and analysed retrospectively in comparison with surgical and pathological results.Results Five of 11 lesions were located in the right adrenal gland,6 in the left.The diameter of the tumors was 4.1—16.0cm with 2 cases10.0cm.The attenuation of the plain scans,two phases contrast scans was 21.9—46.7 HU(with a mean value of 35.3 HU),30.5—65.8 HU(mean value 47.1 HU),and 52.6— 97.0 HU(mean value 74.2 HU),respectively.Four were in the shape of capsule,6 reticular,1 slightly inhomogeneous masses.The irregular tumor vessels of 6 reticular masses were seen in the artery phase. Conclusion The dynamic CT features of primary adrenocortical carcinoma were obvious,dynamic SCT scans could suggest the diagnose.