Membrane fusion mediated by baculovirus gp64 involves assembly of stable gp64 trimers into multiprotein aggregates

The baculovirus fusogenic activity depends on the low pH conformation of virally-encoded trimeric glycoprotein, gp64. We used two experimental approaches to investigate whether monomers, trimers, and/or higher order oligomers are functionally involved in gp64 fusion machine. First, dithiothreitol (DTT)- based reduction of intersubunit disulfides was found to reversibly inhibit fusion, as assayed by fluorescent probe redistribution between gp64-expressing and target cells (i.e., erythrocytes or Sf9 cells). This inhibition correlates with disappearance of gp64 trimers and appearance of dimers and monomers in SDS-PAGE. Thus, stable (i.e., with intact intersubunit disulfides) gp64 trimers, rather than independent monomers, drive fusion. Second, we established that merger of membranes is preceded by formation of large (greater than 2 MDa), short-lived gp64 complexes. These complexes were stabilized by cell-surface cross-linking and characterized by glycerol density gradient ultracentrifugation. The basic structural unit of the complexes is stable gp64 trimer. Although DTT-destabilized trimers were still capable of assuming the low pH conformation, they failed to form multimeric complexes. The fact that formation of these complexes correlated with fusion in timing, and was dependent on (a) low pH application, (b) stable gp64 trimers, and (c) cell-cell contacts, suggests that such multimeric complexes represent a fusion machine.     

64D型半自动闭塞的改进

64D型半自动闭塞存在着区间丢车、尾追、撞车的严重缺陷 ,武钢采用延伸接近区段 ,增设自动复原设施等方法 ,收到了良好的效果。     

Vitelliform dystrophy in a 64-year-old man

A device suitable for the long-time measurement of relative skin humidity is described. This is a simple circuit with a resistance bridge for lithium chloride sensors connected to a digitally steered logic circuit, which causes dried air to stream intermittently through a measuring chamber placed on the skin in such a way that the relative humidity over the skin is maintained at a constant level. The number of switching time periods is proportional to the relative humidity (secretion performance) of the skin and can be counted, recorded, or directly fed into a digital calculator. The apparatus, including a two-channel version with skin temperature recording, has proved useful in sleep investigations under extreme climatic conditions.     

Image-transmission of radiotherapy planning using 64kbps-ISDN videophone

We carried out the image-transmission using the 64kbps-ISDN and two terminals of the videophone installed in Osaka Teishin Hospital and Department of Radiation Oncology, Biomedical Research Center, Osaka University Medical School. The frame speeds (sec./frame) of the videophone are 1.2 for standard resolution with 320 x 200 matrix and 5.0 for high resolution with 640 x 400 matrix. Although the image with 640 x 400 matrix is not enough for the radiation diagnosis such as the chest radiogram, the image is useful for the radiation therapy planning. This system is easy to operate, and will be widely distributed in near future.     

Kernicterus. Anatomo clinical correlation in 64 newborn infants

The case histories and autopsy reports of 64 neonates who died from kernicterus were reviewed. The most outstanding findings were: high incidence of kernicterus with serum indirect bilirubin less than 15 mg.; different clinical picture of the premature in comparison with term neonate; predisposing factors such as respiratory distress and intrauterine malnutrition were often associated in the premature. Preventive, educational and therapeutic measures were discussed at the end.