Electrochemical Detection of Clenbuterol in Pig Liver at Pyrrole DNA Modified Boron-doped Diamond Electrode

The direct detection of clenbuterol（CL） in pig liver without any extraction separation at a pyrrole-DNA modified boron-doped diamond（BDD） electrode is reported. The pyrrole-DNA modified BDD electrode has a strong electrocatalytic effect on the redox reaction of CL. One oxidization and two reduction peaks of CL appear at 340. 2, 299. 8 and 166. 6 mV（ versus SCE）, respectively. The pyrrole polymer alone cannot electrocatalyze the above reaction at a BDD electrode ; the electrocatalytic effect of a BDD electrode modified with DNA membrane is unsufficient for the analytical detection of CL; the replacement of boron-doped diamond by glass carbon makes the electrocatalytic reaction impossible ; the redox process is pH dependent. The influences of various experimental parameters on the pyrrole-DNA modified BDD electrode were investigated. A sensitive cyclic vohammetric response for CL was obtained in a linear range from 3.4 × 10^-6 to 5 × 10^ -4 mol/L with a detection limit of 8.5 × 10^-7 mol/L. A mean recovery of 102. 7% of CL in the pig liver sample solution and a reproducibility of 3.2% were obtained.

Primarily screening and analyzing ESTs differentially expressed in rats' primary liver cancer

Objective： To screen and analyze key express sequence tags （ESTs） which were differentially displayed in every period of SD rats＇ primary hepatic carcinoma and reveal the molecular mechanism of carcinogenesis. Methods： Using diethylnitrosamine （DENA） as a cancerigenic agent, animal models with different phases of primary hepatic cancer were constructed in SD rats. Rats were respectively sacrificed at d 14, d 28, d 56, d 77, d 105 and d 112 after the rats received DENA by gavage, then the livers were harvested. One part of the livers was classified according to their pathological changes, while the other was reserved for molecular mechanism studies on hepatocarcinogenesis. The differentially expressed genes were isolated from both normal and morbid tissues by mRNA differential display technique （DDRT-PCR）. After the fragments were sequenced, bioinformatics were .used to analyze the results. Results： Twelve differentially expressed cDNA fragments were obtained. Nine fragments had the homology with known cDNA clones, especially EST-7 was similar to BN/SsNHsdMCW mitochondrion gene and the identity was 100% which suggested EST-7 may be the part of BN/SsNHsdMCW mitochondrion gene. In contrast, other three fragments （EST-1, EST-3 and EST-5） had extremely low identity to any genes registered in GENBANK databases. Conclusions： BN/SsNHsdMCW mitochondrion gene was expressed in different periods of hepatocarcinogenesis. Moreover, EST-I, EST-3 and EST-5 were suggested to contribute to the development of rat hepatocarcinogenesis, and thus may be candidates of new targets of oncogenes or cancer suppressor genes.

Non-invasive determination of hepatic steatosis by acoustic structure quantification from ultrasound echo amplitude

AIM:To use leptin-deficient(ob/ob) mice with demonstrated differences in steatosis levels to test a new diagnostic method using the acoustical structure quantification(ASQ) mode and the associated analytical parameter,"focal disturbance ratio"(FD-ratio).METHODS:Nine ob/ob mice,at 5,8,and 12 wk of age(n = 3 in each age group),were used as models for hepatic steatosis.Echo signals obtained from ultrasonography in the mice were analyzed by ASQ,which uses a statistical analysis of echo amplitude to estimate inhomogeneity in the diagnostic region.FD-ratio,as calculated from this analysis,was the focus of the present study.FD-ratio and fat droplet areas and sizes were compared between age groups.RESULTS:No fibrosis or inflammation was observed in any of the groups.The fat droplet area significantly(P < 0.01) increased with age from 1.25% ± 0.28% at 5 wk to 31.07% ± 0.48% at 8 wk to 51.69% ± 3.19% at 12 wk.The median fat droplet size also significantly(P < 0.01) increased with age,from 1.33(0.55-10.52) m at 5 wk,2.82(0.61-44.13) m at 8 wk and 6.34(0.66-81.83) m at 12 wk.The mean FD-ratio was 0.42 ± 0.11 at 5 wk,0.11 ± 0.05 at 8 wk,and 0.03 ± 0.02 at 12 wk.The FD-ratio was significantly lower at 12 wk than at 5 wk and 8 wk(P < 0.01).A significant negative correlation was observed between the FD-ratio and either the fat droplet area(r =-0.7211,P = 0.0017) or fat droplet size(r =-0.9811,P = 0.0052).CONCLUSION:This tool for statistical analysis of signals from ultrasonography using the FD-ratio can be used to accurately quantify fat in vivo in an animal model of hepatic steatosis,and may serve as a quantitative biomarker of hepatic steatosis.

Clinical and Experimental Study on Treatment of Fatty Liver of Phlegm-Dampness Stagnation Type by Zhiganle (脂肝乐) Capsule

Objective: To explore the mechanism of Zhiganle capsule (脂肝乐, ZGLC) in treating fattyliver of Phlegm-Dampness Stagnation type. Methods: One hundred and forty-six patients were treated withZGLC, the effects were observed and compared with those treated with Dongbao Gantai (DBGT, 东宝肝泰)tablets as control. The effect of ZGLC on ethionine induced hyperlipemia model rats was also observed. Results:The effect of ZGLC was obviously better than those of DBGT in relieving or removing symptoms, normalizingthe ultrasonic abnormal findings, lowering the serum levels of lipid and enzyme and improving hemorrheologicfunctions. Experimental study showed that ZGLC could reduce the blood lipids, inhibit the lipid deposition inliver. As compared with the model group, level of triglyceride in the ZGLC treatment group were much lowered(P < 0. of ) and the effect was better than those in the control group. Conclusions: ZGLC has the effect of reducing blood triglyceride level, inhibiting lipid deposition in liver and improving hemorrheologic function.Keywods: Zhiganle capsule; Phlegm--Dampness Stagnation; animal model of fatty liver

CT via percutaneous splenoportography: experiment and application

Objective To introduce computed tomography via percutaneous splenoportography (CTSP), a new method for determining hepatic diseases Methods Ten hybrid dogs and 31 patients with primary hepatic cancer (PHC) were included in the study Each dog was examined by CT, computed tomography via arterial portography (CTAP), and CTSP to compare the enhanced density of the liver The 31 patients were examined by CTSP and the appearanec of PHC was compared with their pathological results to evaluate the diagnostic significance of CTSP Results The animal experiment showed that both CTAP and CTSP could obviously enhance the density of the liver ( P <0 01), but no significant difference was observed in the enhanced densities between the two methods ( P >0 05) On the CTSP images of the 31 patients, the density of the livers was increased to 168-192?Hu, whereas the density of the cancers was as low as that on the images of CT scans (<58?Hu) The CTSP findings were consistent with the surgical ones from space occupying lesions The diagnostic value of CTSP was obviously superior to that of general enhanced CT However, it was difficult for CTSP to show nodules less than 1?cm in size located on the surface of the liver or the hepatic portal zone Conclusions Like CTAP, CTSP is also a sensitive method for showing occupant in the liver But the equipments and the procedures are simpler for CTSP than for CTAP CTSP is an alternative procedure in clinical practice