The activities of two histamine-metabolizing enzymes, histamine-N-methyltransferase (HMT) and diamine oxidase (DAO), were examined in various types of experimentally induced cutaneous inflammations ...in guinea pigs. In intact guinea-pig skin, the specific activities of HMT and DAO were 24.8 +/- 1.7 pmol/min per milligram of protein or 0.930 +/- 0.097 pmol/min per milligram of the wet weight of skin specimen, and 6.0 +/- 0.7 pmol/min per milligram of protein or 0.189 +/- 0.011 pmol/min per milligram of the wet weight, respectively. Both enzyme activities were markedly reduced in skin lesions of the Arthus reaction (P less than 0.005), while those in dinitrochlorobenzene allergic dermatitis, croton-oil dermatitis, and the intact areas in Arthus-reaction-induced animals were almost within the normal limits. The activity of HMT decreased linearly with time from the onset of the Arthus reaction, reaching about 20% of the control activity at 48 h; the activity of DAO decreased even from the early stages of the reaction, and this decrease continued throughout first 48 h of the reaction. These results suggest that impaired histamine metabolism in the skin lesions of the reaction plays a distinct role in the formation and development of the Arthus reaction.
Nonviral vectors are safer and more cost-effective than viral vectors but are significantly less efficient, and thus, increasing the efficiency of nonviral vectors remains an important objective. One ...way to overcome this problem is by stimulating the nuclear localization of exogenous genes. Nuclear localization signals (NLSs) are known to be involved in the active transport of exogenous proteins and probes into the nucleus. However, stimulation of nuclear localization of plasmid DNA has yet to be confirmed completely. In the present study, we prepared plasmid DNA-NLS peptide conjugates and adjusted spacer length and number introduced in an attempt to increase transfection efficiency. In comparison to conjugates with unmodified plasmid DNA and short spacers, we found that NLS-plasmid DNA conjugates with covalent bonding by diazo coupling through PEG chain (MW 3400) stimulated complexation with the nuclear transport proteins importin alpha and importin beta . Evaluation of transfection showed higher expression efficiency with plasmid DNA-NLS peptide conjugates than with unmodified plasmids. However, evaluation of intracellular trafficking after microinjection into the cytoplasm showed plasmid DNA-NLS peptide conjugates only within the cytoplasm; there was no NLS-plasmid stimulation of nuclear localization. Our findings suggest that stimulation of plasmid nuclear localization cannot be achieved merely by changing spacer length or chemically modifying plasmid DNA-NLS peptide conjugates. An additional mechanism must be involved.
Examination of barbels of the carp (Cyprinus carpio) revealed cells showing the characteristics of Merkel cells. Some ultrastructural features of these cells suggest a secretory function.
3-Nitrotyrosine (3-NT), a product of peroxynitrite reaction, is abundantly observed in hepatocytes adjacent to human metastatic colorectal carcinoma. To elucidate its biological significance, we ...undertook to identify nitric oxide (NO)-producing cells and apoptosis under oxidative stress. We observed strong inducible NO-synthase (iNOS) immunoreactivity in the hepatocytes adjacent to metastatic tumor, revealing an identical pattern to 3-NT immunostaining. Furthermore, intense 3-NT immunostaining of hepatocytes was associated with apoptosis whereas carcinoma cells near those hepatocytes presented high proliferating-cell nuclear antigen. Our results suggest that contact of metastatic tumor induces apoptosis in adjacent hepatocytes through peroxynitrite, thus permitting the proliferation of cancer cells.
Although it is generally believed that MIG welding of aluminum is more difficult as compared with case of steel, this may probably due to property of bead, arc stability, welding defects, etc. ...However, because of characteristics in light weight and corrosion resistance, MIG welding of aluminum might be utilized in larger extent in production fields such as in automobiles and railroad vehicles. A paper explains problems and precautions to be taken in aluminum MIG welding, such as prevention of blow holes, maintenance in arc stability, etc. Kinds in welding materials and guiding directory in usage are given.
For the first time ever a hybrid system using a 42-V power supply system has been developed for better fuel economy, lower emissions and urban environment. And Toyota Mild Hybrid System (THS-M), ...which is the first mass production vehicle with dual voltage(42V/14V) has been launched to the Japanese market In August, 2001. This paper introduces the system configuration, features and gives actual vehicle evaluation results. The system has a motor generator (hereinafter M/G) connected to the engine crankshaft via a belt, in place of the alternator on a conventional vehicle. The electronic control of the M/G has five functions: restarting the stopped engine, driving the vehicle when starting, driving auxiliaries when the engine Is stopped, power generation during ordinary traveling and regenerative braking on deceleration braking. By restarting the engine via a belt with motor driving control, a smooth starting without discomfort is achieved. Furthermore, using this motor to drive auxiliaries during Idle increases the number of idle stop opportunities. Installing this system on a direct injection 3.0 liter engine with a 5-speed automatic transmission improves fuel economy by about 40% in the Japanese standard urban mode, when compared to the average fuel consumption of vehicles in the same class without the system.
