<b>OBJECTIVESb>To evaluate the inhibitory effect mediated by combination of small interfering RNAs (siRNAs) targeting different sites of hepatitis B virus (HBV) transcripts on the viral replication and antigen expression in vitro.

<b>METHODSb>(1) Seven siRNAs targeting surface (S), polymerase (P) or precore (PreC) region of HBV genome were designed and chemically synthesized. (2) HBV-producing HepG2.2.15 cells were treated with or without siRNAs for 72 h. (3) HBsAg and HBeAg in the cell culture medium were detected by enzyme-linked immunoadsorbent assay. (4) Intracellular viral DNA was quantified by real-time PCR (Polymerase Chain Reaction). (5) HBV viral mRNA was reverse transcribed and quantified by real-time PCR. (6) The change of cell cycle and apoptosis was determined by flow cytometry.

<b>RESULTSb>Our data demonstrated that synthetic small interfering RNAs (siRNAs) targeting S and PreC gene could efficiently and specifically inhibit HBV replication and antigen expression. The expression of HBsAg and HBeAg and the replication of HBV could be specifically inhibited in a dose-dependent manner by siRNAs. Furthermore, our results showed that the combination of siRNAs targeting various regions could inhibit HBV replication and antigen expression in a more efficient way than the use of single siRNA at the same final concentration. No apoptotic change was observed in the cell after siRNA treatment.

<b>CONCLUSIONb>Our results demonstrated that siRNAs exerted robust and specific inhibition on HBV replication and antigen expression in a cell culture system and combination of siRNAs targeting different regions exhibited more potency.

Apoptosis ; Cell Cycle ; Cell Line, Tumor ; DNA, Viral ; biosynthesis ; Flow Cytometry ; Gene Expression Regulation, Viral ; genetics ; Hepatitis B Surface Antigens ; metabolism ; Hepatitis B e Antigens ; metabolism ; Hepatitis B virus ; genetics ; physiology ; Humans ; RNA, Small Interfering ; genetics ; metabolism ; Virus Replication ; genetics

<b>OBJECTIVEb>To assess the effect of temporary occlusion of hepatic blood inflow on hepatic cancer treated with diode-laser induced thermocogation (LITT).

<b>METHODSb>The carcinoma Walker-256 was implanted in 40 SD rat livers. Twelve days later, the animals were randomly divided into 4 groups. Group A received LITT alone; group B received hepatic artery temporary occlusion during LITT; group C received portal vein temporary occlusion during LITT; group D received hepatic artery and portal vein temporary occlusion during LITT. Tumors were exposed to 810 nm diode-laser light at 0.95 watts for 10 min from a scanner tip applicator placed in the tumor. At the same time, the intrahepatic temperature distribution in rats with liver tumors was measured per 2 min during thermocoagulation. Tumor control was examined immediately 7 and 14 d after thermocoagulation.

<b>RESULTSb>There was significant difference of intrahepatic temperature distribution in rats with liver tumors among the 4 groups (P<0.05) except when group C samples were compared with group D samples at each time point, and group B samples were compared with group C samples at 120 s (P>0.05). Light microscopic examination of the histologic section samples revealed three separate zones: regular hyperthermic coagulation necrosis zone, transition zone and reference zone. Compared with the samples in group A and group B, group C and group D samples had more clear margin among the three zones.

<b>CONCLUSIONb>The hepatic blood inflow occlusion, especially portal vein hepatic blood inflow occlusion, or all hepatic blood inflow occlusion considerably increased the efficacy of LITT in the treatment of liver cancer.

Animals ; Laser Coagulation ; Liver Circulation ; physiology ; Liver Neoplasms ; blood supply ; surgery ; Rats ; Temperature ; Time Factors

<b>OBJECTIVEb>To find new potential biomarkers and establish the patterns for the detection of ovarian cancer.

<b>METHODSb>Sixty one serum samples including 32 ovarian cancer patients and 29 healthy people were detected by surface-enhanced laser desorption/ionization mass spectrometry (SELDI-MS). The protein fingerprint data were analyzed by bioinformatics tools. Ten folds cross-validation support vector machine (SVM) was used to establish the diagnostic pattern.

<b>RESULTSb>Five potential biomarkers were found (2085 Da, 5881 Da, 7564 Da, 9422 Da, 6044 Da), combined with which the diagnostic pattern separated the ovarian cancer from the healthy samples with a sensitivity of 96.7%, a specificity of 96.7% and a positive predictive value of 96.7%.

<b>CONCLUSIONSb>The combination of SELDI with bioinformatics tools could find new biomarkers and establish patterns with high sensitivity and specificity for the detection of ovarian cancer.

Adolescent ; Adult ; Aged ; Biomarkers, Tumor ; blood ; Computational Biology ; Female ; Humans ; Lasers ; Mass Spectrometry ; Middle Aged ; Ovarian Neoplasms ; blood ; diagnosis ; Peptide Mapping ; Predictive Value of Tests ; Proteomics ; Reproducibility of Results ; Sensitivity and Specificity

Let G be a weighted graph with adjacency matrix A=[a(ij)]. An Euclidean graph associated with a molecule is defined by a weighted graph with adjacency matrix D=[d(ij)], where for i not = j, d(ij) is the Euclidean distance between the nuclei i and j. In this matrix d(ii) can be taken as zero if all the nuclei are equivalent. Otherwise, one may introduce different weights for different nuclei. Balasubramanian (1995) computed the Euclidean graphs and their automorphism groups for benzene, eclipsed and staggered forms of ethane and eclipsed and staggered forms of ferrocene. This paper describes a simple method, by means of which it is possible to calculate the automorphism group of weighted graphs. We apply this method to compute the symmetry of tetraammine platinum(II) with C2v and C4v point groups.
Algorithms ; Computer Simulation ; Isomerism ; Models, Chemical ; Models, Molecular ; Molecular Conformation ; Nitrogen Compounds ; analysis ; chemistry ; Numerical Analysis, Computer-Assisted ; Platinum Compounds ; analysis ; chemistry

In this work, the surface activity of block copolymer nonionic surfactants (RPE) has been determined, i.e., critical micelle concentration (CMC), surface excess concentration (gamma), surface area demand per molecule (A), surface tension at CMC (gamma(CMC)). A linear decrease of ln[CMC] vs number of oxypropylene units in copolymer molecule was observed. The change in the work of cohesion per oxypropylene group when passing from molecular into micellar state, calculated from the Shinoda equation, was 0.43 kT for the studied compounds.
Colloids ; chemistry ; Epoxy Compounds ; chemistry ; Ethylene Oxide ; chemistry ; Materials Testing ; Micelles ; Molecular Structure ; Polymers ; chemistry ; Structure-Activity Relationship ; Surface Tension ; Surface-Active Agents ; chemistry

Silicon carbide (SiC) ceramic with YAG (Y3Al5O12) additive added by sol-gel method was liquid-phase sintered at different sintering temperatures, and the sintering mechanism and microstructural characteristics of resulting silicon carbide ceramics were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and elemental distribution of surface (EDS). YAG (yttrium aluminum garnet) phase formed before the sintering and its uniform distribution in the SiC/YAG composite powder decreased the sintering temperature and improved the densification of SiC ceramic. The suitable sintering temperature was 1860 degrees C with the specimen sintered at this temperature having superior sintering and mechanical properties, smaller crystal size and fewer microstructure defects. Three characteristics of improved toughness of SiC ceramic with YAG added by sol-gel method were microstructural densification, main-crack deflection and crystal 'bridging'.
Aluminum Oxide ; analysis ; chemistry ; Carbon Compounds, Inorganic ; analysis ; chemistry ; Ceramics ; chemistry ; Crystallization ; methods ; Gels ; chemistry ; Hot Temperature ; Molecular Conformation ; Phase Transition ; Silicon Compounds ; analysis ; chemistry ; Surface Properties ; Yttrium ; analysis ; chemistry

Mg2Ni0.8Cr0.2-x wt.% CoO/Al2O3 (x=0.5, 1, 2 and 3) composites were prepared by mechanically milling sintered Mg2Ni0.8Cr0.2 alloy and CoO/Al2O3 compound for 45 h. The addition of CoO/Al2O3 compound resulted in the good kinetics properties of hydriding/dehydriding reaction of the composites. The composite with 1.0 wt.% CoO/Al2O3 catalyst could reach the maximum hydrogen absorption capacity (2.9 wt.%) within 5 min at 393 K under H2 pressure of 4 MPa, and can desorb rapidly at 493 K. The decomposition and synthesis of hydrogen molecule on Mg2Ni0.8Cr0.2 alloy surface was promoted by addition of CoO/Al2O3 catalyst. In addition, the formation of metallic Ni particles, strain and defects during the ball milling process also resulted in the improved hydrogenation performance of Mg2Ni-based alloys.
Absorption ; Aluminum Oxide ; analysis ; chemistry ; Hot Temperature ; Hydrogen ; analysis ; chemistry ; Kinetics ; Magnesium Compounds ; analysis ; chemistry ; Manufactured Materials ; analysis ; Materials Testing ; Molecular Conformation ; Nitrogen Compounds ; analysis ; chemistry ; Pressure ; Temperature

Bailong Cave with its well-developed Middle Triassic calcareous dolomite's system was opened as a show cave for visitors in 1988. The speleothem scenery has been strongly weathered as white powder on the outer layers. Study of the cave winds, permeability of soil-rock system and the chemical compositions of the dripping water indicated: (1) The cave dimension structure distinctively affects the cave winds, which were stronger at narrow places. (2) Based on the different soil grain size distribution, clay was the highest in composition in the soil. The response sense of dripping water to the rainwater percolation was slow. The density of joints and other openings in dolomite make the dolomite as mesh seepage body forming piles of thin and high columns and stalactites. (3) Study of 9 dripping water samples by HYDROWIN computer program showed that the major mineral in the water was dolomite.
Biodegradation, Environmental ; Calcium Carbonate ; analysis ; chemistry ; China ; Ecosystem ; Geology ; methods ; Permeability ; Soil ; analysis ; Water ; analysis ; chemistry ; Weather

Three types of new high-efficiency phosphate fertilizers were made when pillared clays at certain proportions were added into ground phosphate rock. Chemical analyses showed that their soluble phosphorus content decreased more than that of superphosphate. Pot experiment showed that, under equal weights, the new fertilizers increased their efficiency by a large margin over that of superphosphate. Researches on their structures by means of XRD, IR and EPR spectrum revealed that their crystal structures changed considerably, improving their activity and preventing the fixation of available phosphorus in the soil, and consequently, greatly improved the bioavailability and became the main cause of the increase of biomass.
Aluminum Silicates ; analysis ; chemistry ; Fertilizers ; analysis ; Molecular Conformation ; Phosphates ; analysis ; chemistry ; Soil ; analysis

Pulverized coal reburning, ammonia injection and advanced reburning in a pilot scale drop tube furnace were investigated. Premix of petroleum gas, air and NH3 were burned in a porous gas burner to generate the needed flue gas. Four kinds of pulverized coal were fed as reburning fuel at constant rate of 1g/min. The coal reburning process parameters including 15% approximately 25% reburn heat input, temperature range from 1100 degrees C to 1400 degrees C and also the carbon in fly ash, coal fineness, reburn zone stoichiometric ratio, etc. were investigated. On the condition of 25% reburn heat input, maximum of 47% NO reduction with Yanzhou coal was obtained by pure coal reburning. Optimal temperature for reburning is about 1300 degrees C and fuel-rich stoichiometric ratio is essential; coal fineness can slightly enhance the reburning ability. The temperature window for ammonia injection is about 700 degrees C approximately 1100 degrees C. CO can improve the NH3 ability at lower temperature. During advanced reburning, 72.9% NO reduction was measured. To achieve more than 70% NO reduction, Selective Non-catalytic NO(x) Reduction (SNCR) should need NH3/NO stoichiometric ratio larger than 5, while advanced reburning only uses common dose of ammonia as in conventional SNCR technology. Mechanism study shows the oxidization of CO can improve the decomposition of H2O, which will rich the radical pools igniting the whole reactions at lower temperatures.
Air Pollutants ; chemistry ; isolation & purification ; Carbon Monoxide ; chemistry ; Coal ; Computer Simulation ; Hot Temperature ; Models, Chemical ; Nitrogen Oxides ; chemistry ; isolation & purification ; Oxidation-Reduction ; Temperature