Hierarchical structured α-Al2O3 supported S-promoted Fe catalysts for direct conversion of syngas to lower olefins.

Hierarchical structured α-Al2O3 is shown to be able to effectively disperse and immobilize iron species, in comparison with commercial α-Al2O3. After promotion using an appropriate amount of sulfur, iron catalysts exhibit not only enhanced Fischer-Tropsch synthesis activity and selectivity toward lower olefins, but also increased resistance against carbon deposits.

[Identification of Pu' er tea by Fourier transform infrared spectroscopy].

In the present paper, Fourier transform infrared spectroscopy (FTIR) was used to determine unzymic and zymic Pu'er tea of different grade produced in Simao, Yunan Province. Because of the different processing technology, different proportion of chemical constituents exists in the unzymic and zymic Pu'er tea. And although there is a great mass of similarity in infrared spectrum, the results still show differences in the characteristic peaks of infrared spectrum between unzymic and zymic Pu'er tea. And there is also obvious difference between unzymic Pu'er tea of different grade or zymic Pu'er tea of different grade. According to the studies of the spectral peaks and absorbance ratios, unzymic and zymic Pu'er tea can easily be identified. And different grade of unzymic and zymic Pu'er tea may be classified by the differences in the absorbance ratios of several peaks. FTIR is proved to be a rapid, simple, reliable and non-destructive qualification method, it is suitable for grade identification of Pu'er tea.

N-nitrosodiethylamine-induced pig liver hepatocellular carcinoma model: radiological and histopathological studies.

Experimental research involving animal models plays a critical role in the development and improvement of minimally invasive therapies for hepatocellular carcinoma (HCC). As a large animal, the pig is commonly used for surgery and interventional radiology research. In this study, liver multicentric HCC with cirrhosis was induced in six China Taihu pigs by intraperitoneal injection of 10 mg/kg of N-nitrosodiethylamine once a week for 3 months, followed by a period of 10-12 months without N-nitrosodiethylamine treatment. All pigs were in generally good health until the end of the study. The tumor nodules appeared hyperattenuating in the arterial phase of a dynamic computed tomography (CT) scan. Digital subtraction angiography (DSA) and CT angiography demonstrated that the tumors derived their blood supply mainly from the hepatic artery system. Lipiodol-CT showed Lipiodol retention in tumor areas. The histology and electron microscopic ultrastructure of the chemically induced liver HCC in this study resembled human HCC with a cirrhosis background. An immunohistochemistry study confirmed that the tumors were of hepatocyte origin. All highly, moderately, and poorly differentiated HCC tumors were identified in this study. Cholangiocarcinoma was not seen in any of the animals. Due to its comparable size to human anatomy, the pig liver HCC model would give a better scope for interventional and surgical manipulations than small animal models.

[Anticarcinogenic effect of 20(R)-ginsenoside Rg3 on induced hepatocellular carcinoma in rats].

OBJECTIVE: To explore the anticarcinogenic mechanism of 20(R)-ginsenoside Rg3 in induced liver tumor in SD rat. METHODS: Thirty-five SD rats with induced hepatocellular carcinoma were divided into a control group and 3 dosage groups according to the dosing levels of 20(R)-ginsenoside Rg3. The tumour volume was measured by MR imaging. The apoptotic rat and S-phase fraction and diploid of tumor cell were measured with flow cytometry. Protein expression of PCNA and TNF were evaluated with immunohistochemistry. RESULTS: There was significant difference in tumour volume between the high dosage group and the control group. The average apoptotic rates were 11.08+/-3.78, 13.57+/-3.34, 27.35+/-16.04 and the S-phase fractions were 23.98+/-9.44, 19.73+/-6.62, 14.09+/-3.48 in the low-, medium-, and high-dosage groups respectively. The apoptotic rate was significantly higher in the high-dosage group than in the medium-dosage group and low-dosage group. Before-after comparison showed that the anti-proliferative effects of 20(R)-ginsenoside Rg3 were significant in three treatment groups. The higher positive rats of protein expression with PCNA and TNF were significant difference in the high-dosage group compared to those in the low-dosage group. No significant difference between the medium-dosage group and the low-dosage group. CONCLUSION: 20(R)-ginsenoside Rg3 can noticeably inhibit the proliferation of tumor cells, and efficaciously induce the apoptosis and facilitate necrosis of the tumor cells, and there appears to be a dose dependent effect.

Detection of hypervascular hepatocellular carcinoma: Comparison of multi-detector CT with digital subtraction angiography and Lipiodol CT.

AIM: The purpose of this study was to compare the diagnostic accuracy of biphasic multi-detector row helical computed tomography (MDCT), digital subtraction angiography (DSA) and Lipiodol computed tomography (CT) in detection of hypervascular hepatocellular carcinoma (HCC). METHODS: Twenty-eight patients with nodular HCC underwent biphasic MDCT examination: hepatic arterial phase (HAP) 25 s and portal venous phase (PVP) 70 s after injection of the contrast medium (1.5 mL/kg). They also underwent hepatic angiography and intra-arterial infusion of iodized oil. Lipiodol CT was performed 3-4 wk after infusion. MDCT images were compared with DSA and Lipiodol CT images for detection of hepatic nodules. RESULTS: The three imaging techniques had the same sensitivity in detecting nodules >20 mm in diameter. There was no significant difference in the sensitivity among HAP-MDCT, Lipiodol CT and DSA for nodules of 10-20 mm in diameter. For the nodules <10 mm in diameter, HAP-MDCT identified 47, Lipiodol CT detected 27 (chi2 = 11.3, P = 0.005<0.01, HAP-MDCT vs Lipiodol CT) and DSA detected 16 (chi2 = 9.09, P = 0.005<0.01 vs Lipiodol CT and chi2 = 29.03, P = 0.005<0.01vs HAP-MDCT). However, six nodules <10 mm in diameter were detected only by Lipiodol CT. CONCLUSION: MDCT and Lipiodol CT are two complementary modalities. At present, MDCT does not obviate the need for DSA and subsequent Lipiodol CT as a preoperative examination for HCC.

Hepatocellular carcinoma treated with interventional procedures: CT and MRI follow-up.

In the past decade, a variety of interventional procedures have been employed for local control of hepatocellular carcinoma (HCC). These include transcather arterial chemoembolization (TACE) and several tumour ablation techniques, such as percutaneous ethanol injection (PEI), radio-frequency ablation (RFA), or percutaneous microwave coagulation therapy (PMC), laser-induced interstitial thermotherapy (LITT), etc. For a definite assessment of the therapeutic efficacy of interventional procedures, histological examination using percutaneous needle biopsy may be the most definite assessment of the therapeutic efficacy of interventional therapy, however, it is invasive and the specimen retrieved does not always represent the entire lesion owing to sampling errors. Therefore, computed tomography (CT) and magnetic resonance imaging (MRI) play a crucial role in follow-up of HCC treated by interventional procedures, by which the local treatment efficacy, recurrent disease and some of therapy-induced complications are evaluated. Contrast enhanced axial imaging (CT or MR imaging) may be the most sensitive test for assessing the therapeutic efficacy. The goal of the review was to describe the value of CT and MRI in the evaluation of interventional treatments.