Plasma lipid peroxides in the operation of esophageal cancer]

Lipid peroxides are formed by autooxidation of polyunsaturated fatty acids found primarily in cell membranes. An increase level of lipid peroxides in the tissue therefore reflects membrane damage. We reported that water immersion restraint rats caused significant increase of gastric mucosal lipid peroxide which reflected on gastric mucosal injury. The gastric mucosal injury is also known as the post-operative complication due to physical stress. So we studied plasma lipid peroxide and its related substances in the operation of esophageal cancer. Lipid peroxide levels increased significantly in pre- and post-operation but temporal decrease was found during the operation. Vitamin E is thought to be an important structural component of biologic membranes and is believed to act as a free radical scavenger in lipid peroxidation. Vitamin E also increased in the patients of esophageal cancer and decreased significantly during the operation. Superoxide dismutase changed frequently during the operation but there was no deficit tendency in its changes. Catalase levels also changes frequently and showed temporal but statistical elevation after the operation. These results indicated that lipid peroxidation may contribute to the development of organic damage in the operation of esophageal cancer.     

Gas phase oxidation of benzene to phenol using Pd-Cu composite catalysts. Effect of temperature,feeding gas and catalyst composition

Catalytic oxidation of benzene in the gas phase has been studied as a function of the catalyst composition, reaction temperature and the feed conditions of reactant gases, hydrogen, oxygen, benzene as well as diluting inert gas. The catalyst tested is composed of Pd and Cu(I) ions, both of which are supported on silica gel. If one of the two metal species is lacked from the catalyst, no catalytic activity appears. The product is almost exclusively phenol and some accompanying benzoquinone, in particular at lower temperatures, as minor byproduct.On leave from Hua-Dong Institute of Technology, Nanjing, People's Republic of China.     

Performance of ternary PtRuRh/C electrocatalyst with varying Pt:Ru:Rh ratio for methanol electro-oxidation

Highly dispersed ternary PtRuRh/C anode catalysts for direct methanol fuel cells were prepared with various contents and their electro-catalytic activities towards methanol oxidation at 25 °C and 60 °C were examined to investigate the influence of the catalyst composition. Electrocatalysts were prepared by a co-impregnation method using ethanolic solutions of metal precursors and carbon black followed by pyrolysis under reducing conditions. X-ray diffraction analysis revealed that the fcc peaks shifted to higher diffraction angles with increasing Rh content, indicating the alloying of Rh into the fcc structure. In terms of the mass specific current density, the activity towards methanol oxidation differed significantly depending on the catalysts composition and cell temperature. The catalyst prepared at a ratio of Pt:Ru:Rh = 1:1:2 exhibited the highest activity at 60 °C of 155 A (g-Pt)⁻¹ at 0.5 V vs. RHE.     

Histochemical demonstration of different types of poly-N-acetyllactosamine structures in human thyroid neoplasms using lectins and endo-beta-galactosidase digestion

Blood-group-related antigens expressed in papillary carcinomas and other types of neoplasm of the human thyroid glands have been shown to be carried by poly-N-acetyllactosamines containing a linear domain susceptible to endo-beta-galactosidase digestion. To make clear more precisely the backbone poly-N-acetyllactosamine structures, labelled lectins specific to different types of these structures and specific to core structures with beta 1-6GlcNAc branching of N- and O-linked glycoproteins were employed in conjunction with prior endo-beta-galactosidase digestion on formalin-fixed, paraffin-embedded neoplasms of the human thyroid glands. In papillary carcinomas, Datura stramonium agglutinin (DSA) and succinyl wheat germ agglutinin (Suc-WGA) reacted most consistently and frequently with papillary carcinomas from all the individuals examined. Pokeweed mitogen (PWM) likewise stained the cells of papillary carcinomas from all the individuals examined, but in some individuals the number of lectin-reactive cells were very small. Lycoperscion esculentum aggultinin (LEA), Solanum tuberosum agglutinin (STA), Phaseolus vulgaris agglutinin L (PHA-L) and Artocarpus integrifolia agglutinin (jacalin) similarly bound to the cancer cells from most of the individuals, and in these cases the number of reactive cells was usually much more restricted than was the case with DSA or PWM. In adenoma and other types of carcinoma, such as follicular carcinomas, these lectins specific to poly-N-acetyllactosamine exhibited slight or no reactivity with the cells, whereas PHA-L and jacalin similarly bound to the cells of adenomas and carcinomas from most of the individuals examined. Prior digestion with endo-beta-galactosidase completely eliminated or markedly reduced the reactivity with PWM and LEA in papillary carcinomas. Reactivity with DSA, Suc-WGA, STA, PHA-L and jacalin was slightly reduced or not at all affected by enzyme digestion. These results confirmed that poly-N-acetyllactosamine species found in papillary carcinomas are quite different from those in other types of thyroid neoplasm, suggesting that at least three different types of poly-N-acetyllactosamine, that is, linear unbranched short and long sequences and highly branched ones are produced in these cells.     

A molecular orbital study on the chemical interaction across the indomethacin/silica interparticle boundary due to mechanical stressing

A discrete variational-Xα (DV-Xα) method was applied to elucidate the formation of C-O-Si bridging bonds, produced when a silanol group of SiO₂ comes close enough to react with a carboxyl group of indomethacin (IM). A decrease in the coordination number (CN) of oxygen atoms per silicon atom at the SiO₂ surface increased the net charge (NC) of the silanolic hydrogen atom and decreased the bond overlap population (BOP) between the silanolic oxygen and hydrogen atoms. These changes favored the formation and stabilization of C-O-Si bridging bonds with simultaneous dehydration. The computational results agreed well with our previous experimental study of a ground indomethacin-SiO₂ mixture to obtain a better solid dispersion of the drug.     

Photo-rechargeability of film electrodes prepared by pulsed laser deposition

The film electrodes of TiO₂, which have two functions of opto-electric conversion and storage of electrochemical energy, were prepared by pulsed laser deposition. To investigate the relationship between the photo-rechargeability and the surface structure, the TiO₂ film electrodes with different surface morphology were prepared by changing the inert gas pressure during the deposition. The photo-charged quantity was found to be proportional to the third power of the rms of surface roughness. The results suggest that not only the surface but also the interstices between crystal grains near the surface contribute to the photo-charging with low photo-emf.     

Scintillation properties of Tm-doped Lu3Al5O12 single crystals

Using the micro-pulling-down (μ-PD) method, Tm-doped Lu₃Al₅O₁₂ (Tm:LuAG) single crystals were grown to examine their scintillation properties. In transmittance spectra, they exhibited about 80% transparency in the wavelengths longer than 320 nm and five absorption lines due to Tm³⁺ 4f–4f transitions were observed. ²⁴¹Am α-ray excited radioluminescence spectra were measured and intense 4f–4f emission peaks were observed with the host emission. When excited by ¹³⁷Cs γ-Ray to obtain pulse height spectra, Tm 1% doped LuAG showed the highest light yield coupled with a photomultiplier (PMT) or a silicon avalanche photodiode (Si-APD). The light yield was estimated to be 5800 and 7300 photons/MeV for PMT and Si-APD, respectively. Decay time profiles consist of two exponential components and the fast and slow components are considered to be attributed to the host and the combination of the host and Tm³⁺ 4f–4f emission, respectively.     

Photosensitized hydrogen evolution from water using a single-walled carbon nanotube/fullerodendron/SiO2 coaxial nanohybrid

A coaxial nanohybrid consisting of a single-walled carbon nanotube (SWCNT), fullerodendron, and SiO(2) shows high-efficiency light-driven hydrogen evolution from water. Upon visible light irradiation, SWCNT/fullerodendron/SiO(2) coaxial nanohybrid shows hydrogen evolution activity in the presence of methyl viologen (MV(2+)), benzyldihydronicotinamide (BNAH), and a colloidal polyvinyl alcohol(PVA)-Pt.     

Nanotrap and mass analysis of aromatic molecules by phenyl group-modified nanoparticle

To functionalize the surface of nanoparticles with phenyl groups for subsequent cross-linking with aromatic molecules by mutual interactions, we prepared functional nanoparticles (d = 3 nm) by silanization with phenyl-triethoxysilane. The nanoparticles had Fe(2)O(3) cores conjugated to phenyl groups; this was confirmed by Fourier transform infrared (FT-IR) spectroscopy and absorption spectrophotometry. The typical C-H and C-C peaks and the absorption at 240 nm, which corresponds to aromatic rings, were detected in the spectroscopic results for the phenyl group-modified nanoparticles. The nanoparticles could ionize aromatic (colchicine, reserpine, and bradykinin peptide) and nonaromatic (L-α-phosphatidylethanolamine,dioleoyl, and polyethylene glycol) molecules by nanoparticle-assisted laser desorption/ionization mass spectrometry. The nanoparticles worked as a selective trap and an ionization-assisting reagent in mass spectrometry for the aromatic molecular targets.